Explosions in Warships During the War

The following has been extracted from CB 1515 (24) The Technical History and Index, Volume 2, Part 24 "Storage and Handling of Explosives in Warships" (October, 1919). The "Technical History," as it's usually referred to, is a series of documents written by the Technical History Section of the British Admiralty shortly after the First World War. There is a complete set in the Admiralty Library, as well as portions in the Imperial War Museum, and elsewhere.

As you read this, keep in mind that it was written in 1919, and more recent research may well have uncovered additional facts. Nevertheless, the conclusions are generally in keeping with modern thought.

92. Analysis of Causes of Explosion. - The following table shows the explosions which occurred during the war and gives briefly the nature and, where known, the cause of each disaster:-

93. Loss of H.M.S. Bulwark. - On November 26, 1914, HMS Bulwark was lying at a buoy in the River Medway. At 7.53 a.m. she suddenly blew up, and when the smoke resulting from the explosion had cleared no trace of the ship remained beyond a mass of wreckage floating around the buoy to which she had been moored. Of the ship's company of over 750 officers and men, no officers and only a very few men were picket up alive, and of these only nine were in a fit state to give any coherent account of the accident. At the time of the explosion most of these men were in the fore part of the ship. The survivors all stated that they heard a rumbling noise and saw a flash or flame and then knew nothing more until they found themselves in the water. The accounts of a large number of eye-witnesses all agree that the first thing seen was a bright yellow flame in the vicinity of the mainmast, accompanied or immediately followed by a rumbling explosion not unlike a distant thunderclap. The stern of the ship was certainly seen to come out of the water, and the whole ship was immediately enveloped in an enormous cloud of smoke. When this smoke had cleared, the ship had disappeared, but at low water small parts of the wreck were visible.

Examination of the wreck by divers showed that the ship had been literally blown to pieces. Fragments were distributed over a large area of the river bottom, though none of the wreck was found to obstruct the fairway. Bad weather and adverse tides hampered the diving operations to a large extent, and very little was salved from the wreck before the operations were finally abandoned.

First opinions regarding the cause of the disaster tended to attribute it either to sabotage or enemy action. A very circumstantial report of the presence of an enemy submarine in the river, close to the ships, was made by an officer and boat's crew of HMS Agamemnon. They asserted that they saw a periscope and attempted to close it, whilst on their way to the scene of the disaster. The story, however, did not bear sifting, and the court of inquiry dismissed it as improbable. Evidence of all who witnessed the explosion agreed that there was no column of water seen outside the ship, such as would have arisen if a torpedo had struck her. The evidence was, in fact, conclusive that the explosion had been internal.

No facts were brought to light to support the suspicion that the disaster was due to an act of sabotage. Certain inquiries led to the arrest of an ex-naval officer, but the suspicion proved to be groundless. Careful scrutiny into the history of all parcels, &c., which had recently been delivered to the ship, led to nothing suspicious being revealed, and sabotage can be safely rules out from all possible causes of the loss of the ship.

A complete list of the lot numbers of all the cordite on board HMS Bulwark had been left by the gunner of the ship with the Naval Ordnance Officer at Portsmouth as recently as September 1914, and as records had been kept of the supplies made since that date, it was possible to trace the antecedents of all the cordite in the ship. Some of this cordite was old, but it had all given very good heat test, and there was no reason to doubt the stability of any of it. The only F.F. (fire-first) cartridges on board HMS Bulwark were four 6-inch half-charges of a certain lot and no heat tests had been recorded under 21 minutes. It was made F.F. in accordance with the regulations, it having been on the China Station for over two years, although the heat test before issue to HMS Bulwark was over 30 minutes.

The gunnery log of the ship was recovered, and this contained a record of the magazine temperatures for the past year. These temperatures had always been normal, and had only on rare occasions reached 70º F., the highest temperature ever recorded being one of 74º F. In view of these known facts, the spontaneous combustion of any of the cordite was regarded as highly improbable.

The ammunition passages of this class of ship became considerably heated when under steam, and observations made in HMS London, a sister ship, under the same conditions as regards boilers alight, &.c, which obtained on board HMS Bulwark at the time of the accident, showed that the air temperature in these passages varied from 70º to 84º. The bulkheads in the vicinity of certain steam pipes were found to be at temperatures up to 120º. Close to these spots hooks were fitted for hanging shell bags, and it was found that since the outbreak of war it had been the practice in HMS London (and presumably also in HMS Bulwark, as the organisation of the ships was identical) to hang a number of 6-inch charges in K.A. bags during the day. This cordite, which formed the ready-use supply for the upper deck casemates, was sent up to the casemates during the night and sent down again by day. The cordite bags were prevented from coming into actual contact with the hot bulkhead by 2-inch wooden battens, and although the practice of stowing cordite under these conditions was undesirable, there are no reasons for believing that the temperatures to which the cordite had been subjected had caused such rapid deterioration as to result in spontaneous combustion in the short period during which the cordite had been so stowed.

It appeared that it had been the practice to exercise the ammunition-supply parties for the 6-inch guns at drill, using live cartridges. In doing this, the various lots of cordite had become mixed, and on the day before the accident a large "gunner's party" was employed in HMS Bulwark sorting out the cartridges in both the forward and after 6-inch magazines. This operation was performed in the two cross-passages and was not completed during the day. Men were employed at the same work in the early hours of the 26^th, and from the evidence of two of the survivors, who happened to visit the ammunition passages about a quarter of an hour before the explosion, it was ascertained that a pile of about 30 bare 6-inch charges remained in both the forward and the after cross-passages. When, at a few minutes before 8 o'clock, the ships company was sent to breakfast, these charges were left in the cross-passages with a sentry on them.

The position as regards cordite at the time of the accident was thus as follows:-

In each main deck casemate there were 20 rounds, either in K.A. cases or in magazine cases. At each end of both cross-passages there was another 20 rounds in K.A. cases. These were hung on the hooks previously referred to, immediately below the ammunition hoists to the upper-deck casemates. In each cross-passage there was a pile of about 30 bare full charges, with a sentry on them. It was not clearly ascertained whether the 6-inch magazines had been closed when the hands were piped to breakfast, but the probability is that they were not. It was also ascertained that in order to facilitate the rapid supply of ammunition to the guns it was the practice to keep a proportion of the lids of the cordite cases in all the magazines permanently off.

As regards shell, 20 were stowed in each casemate and a large number were hung on hooks in the ammunition passages. These shell were equal proportions of common and lyddite, and the latter had recently fuzed. No suspicion attaches to the shell, although it was discovered that it was the practice to remove the caps and pins of the No. 18 fuzes in the lyddite shell on going to night action stations.

At about 7.45 a.m. the ship's company was sent to breakfast and a few minutes afterwards the explosion occurred. there is little doubt that the initial explosion was a cordite one and that it started in the after part of the ammunition passages. As above described a train of exposed cordite was laid round the ship and by some means one of these cartridges became ignited and so caused the disaster. What the actual cause of the ignition of the cordite was it is impossible to say definitely, but the fact that the ship's company had just been sent to breakfast and were therefore allowed to smoke cannot be entirely ignored.

The court of enquiry which investigated the case immediately after the accident stated that they regretfully had to express the opinion that the loss of the ship was due to carelessness on the part of the dead officers who had been in charge of the gunnery department of the ship, and it is feared that to this and no other cause can the disaster be attributed.

94. Loss of HMS Natal.- On December 30, 1915, HMS Natal foundered and became a total loss after a very heavy explosion which was preceded by a smaller one. The ship was at the time lying at anchor at Cromarty Firth, and the first event which attracted attention to her at about 3.20 p.m., was a puff of white smoke rising near or immediately before her mainmast as high as the tops of the funnels. Very shortly afterwards flames shot up abaft the mainmast to a great height, with a rumbling noise not unlike rolling thunder. This was immediately followed by dense volumes of yellow-brown smoke. the ship at once settled won by the stern, remaining upright until the quarterdeck was awash, when at 3.24 p.m. she commenced heeling steadily to port and went over to an angle of about 70º, in which position she hung for about a minute. Her mainmast then went over the side, and she turned over and foundered.

From the evidence of eyewitnesses and from the subsequent examination of the wreck by divers, there can be no doubt that the loss of the ship was due to an internal and not to an external explosion. This explosion appears to have originated in either the 3-pdr. and small-arm magazine or the after 9.2 magazine. The evidence regarding the noise made by the explosion and the colour and odour of the smoke supports the view that it resulted from the ignition of cordite and was in fact a cordite explosion.

Assuming that the immediate cause of the explosion was the ignition, by some means, of cordite in one of the after magazines, such ignition might be due either to a fire in the magazine or to spontaneous combustion of the cordite or other explosive stowed therein.

A very exhaustive enquiry was carried out into the ammunition of all types which was known to have been onboard HMS Natal, with the following results:-

The 9.2 and 7.5 shell were filled either with T.N.T., lyddite, or powder. None of these shell had been found to be specially liable to spontaneous fracture, and the explosives with which they are filled are not at all sensitive or liable to deterioration. The fuzes used in these shell require severe shock to fire them.

The filled shell for the 3 and 6-pdr. guns were either lyddite or powder filled, and no suspicion attaches to them. Among the light Q.F. ammunition there were some cases of "Day Tracer" shell, and it is known that some of them were stowed in the after 3 and 6-pdr. magazine. These shell have a tracer cavity filled with turpentine dye, and provided with a very small outlet in the base of the shell. The outlet is supposed to be absolutely sealed until the shell is fired from the gun. If the shell leaked, the turpentine escaping through the outlet in the base of the shell would have access to the cordite in the cartridge case. Experiments have shown, however, that turpentine, even in contact with cordite, has no deleterious effect. No evidence of a smell of turpentine was forthcoming, and the shell in question had not been subjected to rough usage, nor has any case occurred of similar shell being known to leak. The presence of these shell can therefore be safely ruled out as a cause of the explosion.

Some of the small-arm ammunition on board was of Japanese make, and suspicion was directed towards it for this reason. Experiments showed, however, that when cartridges were exploded electrically in the centre of the boxes, in different positions relative to the remainder of the cartridges, in no case was the explosion extended beyond the cartridge fired. The suspicion attaching to this ammunition was therefore removed.

Nothing abnormal was discovered as regards the other explosives on board, such as fireworks, mines, warheads, wet and dry guncotton, &c., and all the evidence obtainable showed that all these were in their proper places of stowage.

As regards cordite, a considerable amount of "First Use" cordite was on board, including cartridges of seven lot numbers for the 9.2 B.L., three for the 7.5 B.L. and two for the 3-pr. Q.F. guns. Of these, one 9.2 lot had been sent in for test and had been returned to HMS Natal sentenced F.F. (fire first). ON the whole the cordite on board was getting old, though none of the periodical tests had given any cause for apprehension in the state of the knowledge then available. As regards the "First Use" cordite, the number of tests which had been recorded were very few - much fewer than usual. In the interval of 20 months before the accident, only four samples had been landed for test. This was partially due to the fact that periodical tests were suspended for a period of about six months at the commencement of the war, and also it was revealed that no fewer than six different gunners had been in charge of the magazine records of HMS Natal during this period of 20 months, and that the magazine records were in an incomplete state. Some of the "First Use" and "Fire First" cordite had been a year on board by April 1915, and still remained in the ship up to December 30, 1915, the date of the accident. Some of this cordite was therefore neither tested, fired, nor returned for over 20 months from the date of its receipt. This was an undesirable state of affairs, which entailed risks which would have been avoided if the existing orders had been strictly adhered to.

The above facts led to a very careful scrutiny of the Cordite Regulations and to the withdrawal of "Fire First" and "First Use" cordite from HM seagoing ships. The new Cordite Regulations, which are now embodied as an appendix to the Naval Magazine Regulations, contain clauses which guard against the possibility of any cordite remaining ob board HM Ships without test beyond its allotted period, and the importance of carrying out these regulations with the utmost strictness cannot be exaggerated.

The possibility of a fire having occurred in HMS Natal previous to the accident was investigated and no evidence was forthcoming of anything of the kind. The general arrangements to guard against fire were efficient, and at the time of the accident everything was normal on board the ship. A large number of officers and men were ashore, and this reduced the casualties, which were, however, very heavy.

Only one magazine had been opened during the afternoon, and it was probably open at the time of the accident. This was the after 7.5 magazine, in which a magazine sweeper was adjusting the stowage of some empty cases. This man had been visited twice during the afternoon by the gunner of the ship and nothing abnormal was observed in this particular magazine. The system of the magazine sweepers then in vogue in HMS Natal was not usual on board HM Ships, and has since been forbidden. The system opened the way to many irregularities and required the strictest supervision, especially as it appears to have been the practice to allow the sweepers themselves to obtain the magazine keys from the sentry.

Many other minor points were investigated, but none led to any definite results. No suspicion of sabotage appeared during the investigation.

The only certainty is that the ship was lost as the result of an explosion of cordite in one of her after magazines. The actual cause of the explosion has not been definitely ascertained, but the spontaneous ignition of some of the cordite cannot be eliminated as a possible cause of the disaster.

95. Loss of HMS Vanguard. - At about 11.20 p.m., on July 9, 1917, HMS Vanguard, whilst lying at anchor in the Fleet Anchorage at Scapa Flow, blew up and sank. The disaster occurred without any warning. A flame was observed just abaft the foremast, followed after a very short interval by a heavy explosion accompanied by a great increase of flame. A large quantity of fragments was blown up abaft the foremast. A second explosion followed immediately, which considerably increased the volume of flame and smoke. An enormous amount of smoke followed the explosions and entirely obscured the ship. By the time this smoke had cleared away the ship had sunk. No one actually saw the ship sink, but there is evidence that she went down by the head. Of those who were on board at the time, only one officer and two men were picked up alive, and the officer died very shortly afterwards.

The Court of Enquiry, which was assembled immediately after the loss of the ship, was unable to form a strong opinion regarding the actual cause of the explosion, but they were able to point to many circumstances, any one of which might have led to the disaster. They expressed the opinion that there was no doubt that the immediate cause of the loss was the ignition of cordite, and that this ignition might have been brought about by one of the four following means:-

• The ignition of the cordite due to an avoidable cause.
• Abnormal deterioration due to a charge having, undetected, been subject to abnormal treatment during its life.
• The act of an enemy agent, probably outside the ship.
• The ignition of some of the cordite owing to its becoming unstable.

At the end of July 1917 a Committee was appointed at the Admiralty consisting of:-
Captain F. C. Dreyer, CB, RN, Director of Naval Ordnance.
Major A. M. C. Cooper-Key, CB, Chief Inspector of Explosives (Home Office).
Mr. A. C. Clausen, KC.

"To consider the report of the 'Vanguard' inquiry and the steps which it is considered should now be taken to increase the safety of the magazines of HM Ships."

The Committee, after conducting an exhaustive research into all possible aspects of the disaster, reported at the end of February 1918, and their report has been published in CB 01429.

Owing to the urgency of the matter it was not possible to await the report of the above Committee before action was taken in a good many directions. Flag Officers commanding all squadrons forwarded proposals for the better safeguarding of the magazine afloat, and these proposals were carried out in so far as the exigencies of the service in war time permitted. Certain matter which it was desired to put to practical test were embodied in the experiments in HMS Vengeance, which were carried out during the latter part of 1917, and which were started originally for the solution of problems arising out of the Battle of Jutland.

The steps which had been initiated before the accident to withdraw certain classes of cordite from ships, were pressed on with energy, and the revision and republication of the Naval Magazine Regulations in one volume was completed.

The steps which were taken may be classified under three headings:-

(A) Improvements in the stability of explosives issued to HM Ships.

(B) Improvements in storage conditions on board.

(C) Provision for adequate safeguarding of all explosives on board.

These matters are all dealt with in detail in other parts of this pamphlet [Editor's Note: not reproduced] under their appropriate headings, but it is as well to recapitulate here, very briefly, the action taken following directly from the loss of HMS Vanguard.

(A) Some three months before the "Vanguard" explosion considerable improvements had been instituted in the manufacture of cordite by the introduction of the use of clean carded sliver cotton, cracked mineral jelly, and the acceptance of only guncotton which had been nitrated for 2 ½ hours, and also in the appointment of resident inspectors to watch the manufacture in all its stages. At the same time, arrangements were made for the withdrawal of some 6,000 tons of old cordite, replacement being made by cordite manufactured under the new conditions as soon as it was available. After the "Vanguard" explosion, action in these matters was expedited and the exchange was completed in ships of the Grand Fleet by March 1918, and all ships by September 1918.

The details of this procedure will be found in CB 01429.

(B) The steps taken may be divided under three headings:-

(a) Revision of regulations governing the care and stowage of explosives, routine of inspection, taking of temperatures, and magazine log.

(b) Structural alterations to ventilating and cooling trunks, lagging, alterations of stowage in magazines and adjacent compartments, and fitting drenching arrangement.

(c) Improvements in cordite cases and removal of all cases not satisfactorily weakened.

(d) Improvements have been introduced in regard to locking arrangements of magazines and their means of access, and stringent regulations have been issued for supervision of access to and searching of compartments.

Although no facts have been brought to light to indicate that the cause is to be attributed either to the malice of an enemy agent, the act of a lunatic, or to carelessness in handling explosives on shore or after they were supplied to the ship, the lesson of the disaster to HMS Vanguard is that, both in peace or war, so long as a ship has explosives on board, the possibility of the existence of such causes always remains. Therefore every precaution which can be taken must be taken. So far cas can be foreseen, all such precautions are now in force.

96. Loss of HMS Glatton. - At about 6 p.m. on September 16, 1918, an explosion occurred on board HMS Glatton, then lying in Dover Harbour. This was followed by a severe fire involving the whole of the amidship part of the ship. Attempts to deal with the fire failed, and as it was found impossible to flood the after magazines, and there was danger of a further explosion in these which might cause severe damage to the town and to certain other vessels which were in close proximity loaded with oil and ammunition, the ship, at about 8 p.m., was torpedoed and sunk.

She had been commissioned on August 31, 1918, at Newcastle; between the 6^th and 8^th of September she had completed with stores and ammunition, and, after experiencing bad weather on her way south, she arrived at Dover on September 11. She did not proceed to sea again. She had taken in some coal on the day of the explosion.

Since the ship had been so recently commissioned; and all stores, ammunition, and fuel had been taken on board at Newcastle, careful inquiry was made into the arrangement for fuelling, ammunitioning, and fitting out the ship, and regarding the personnel employed in doing so. The result of the inquiry showed that neither the nature of, nor any operation in connection with, the coal, oil fuel, provisions, or stores could in any way be connected with the cause of the explosion.

As regards the ammunition, the ship having commissioned such a short time before, and having carried out no firings except gun trials, it was known for certain exactly what ammunition was on board her. An inquiry was held into the antecedents of all this ammunition, and as it was certain that only the 6-inch magazine and shell rooms amidships were affected by the explosion, the investigation was reduced to within well-defined limits, since the ammunition which had been stowed in these positions was known.

As regards the cordite, only four "lot" numbers of cordite had been supplied to the ship, and it was possible to call in all cordite remaining of these lots and to have it examined and tested. The results of the examination and tests showed that the cordite was normal, and it should be remembered that it had only been on board for about 10 days when the explosion occurred. To suppose that this cordite spontaneously ignited would be to assume a thing which as absolutely unprecedented and contrary to an enormous bulk of experience.

As regards shell, it was not possible to trace the date and place of manufacture and filling of all the 6-inch shell supplied to the ship, but from previous experience with shell of this type, and from the evidence of the nature of the first explosion which occurred, it is certain that the explosion did not originate amongst the shell. There were 10 star shell stowed in the 6-inch shell room, and a special investigation was held in regard to these without revealing any defects. Also, experiments which were carried out to ascertain the effect of exploding star shell in contact with either high-explosive or powder-filled shell produced negative results. The conclusion arrived at was that no suspicion fastens on any shell in the ship.

An examination of a large number of No. 44 and No. 18 fuzes of the same lot numbers as those supplied to HMS Glatton was carried out to ascertain if any were without the proper safety arrangements, so that in the case of a drop or blow they would be liable to be set in action and explode the shell. This would assume that one or more men were at work in the shell room at the time of the explosion, but the time of day and the general circumstances rendered this very improbable. The examination of these fuzes produced no results, and removed any suspicion from them.

Some fireworks were probably stowed in the 6-inch shell rooms concerned, but the fireworks supplied were all of service pattern and no suspicion attaches to them.

An inquiry was held into the precaution taken against access by unauthorised persons to the fuel, ammunition, and stores intended for the ship. No evidence was forthcoming suggesting any attempt at sabotage, and although access by unauthorised persons to these stores was possible, there was no ground warranting the view that the explosion was in any way traceable to this.

HMS Glatton was built for a foreign Government, and differed in design from any of our own ships in that the magazines and shell rooms for the two amidship 6-inch turrets were placed between the engine room and after boiler room, without any air spacing between. The magazine was protected by being lined with wood, and the space of about 4 ½ to 5 inches between the bulkhead and the wood lining was filled with granulated cork, as an insulating material

The evidence clearly located the explosion in the position of the midship 6-inch magazine and shell room, and it is clear that no other explosion occurred. Nothing was disclosed which in any way connected the fuel, stores, or shell with the explosion, and it was therefore concluded that it originated in the midship 6-inch magazine. There was no evidence of anything abnormal occurring in the ship prior to the explosion. The roof of "Q" turret was partly blown off. The superstructure was ablaze in a very short time after the explosion, and the paraffin stored in the superstructure was doubtless a contributory cause in bringing this about.

Evidence of those who were on board at the time showed that a flash was seen before any noise was heard. The whole of the after part of the ship was filled with smoke, and flame reached as far aft as the captain's cabin. Flash extended as far forward as the sick bay and the forward mess decks. As regards the noise, it is variously described as one or more small explosions followed after a perceptible interval by one or more larger ones. No great vibrations or shaking of the ship was noticed by those on board.

Investigations showed that the temperature of the 6-inch magazine as recorded by temperature tube had been quite normal, and that it was, in fact, one of the coolest magazines in the ship. The shell rooms alongside the magazine were, however, inclined to be hot, though not abnormally so, on account of the feed tanks which adjoined them.

It came to light that it had been the practice in HMS Glatton, after cleaning fires, to place clinker and ash in the after boiler room against the after bulkhead, in a pocket between two groups of pumps. This pocket was underneath the ash hoist and was, in fact, the only place in the stokehold where it was possible to stow the ashes preparatory to hoisting them on deck.

This led to a critical examination being made of the magazine and stokehold bulkheads of HMS Gorgon, a sister ship, which had been some months in commission. The wood lining of the magazine bulkhead in HMS Gorgon was removed, and it was found that the paint on the magazine side of the bulkhead was blackened and blistered in three distinct and separate places, these places being opposite the pocket used for clinker and ash in the stokehold. On dismantling the wood lining, no cork lagging was found over a space about 6 feet in width, the greater part of which was abreast the pocket. Besides this, a number of old newspapers were found stuck behind the lining. Further, there was a hole in the bulkhead, ½ inch in diameter, about 4 feet to port of the centre of the pocket and on the same level. This was in HMS Gorgon, and as HMS Glatton was built and completed at the same time and by the same firm, it is impossible to avoid the inference that the same condition of affairs had probably existed in the latter ship.

The condition of the paint on the bulkheads of HMS Gorgon was such that (as was proved by experiment by the National Physical Laboratory) the bulkhead must have been at temperatures of at least 400º Centigrade, and that higher temperatures than this had probably been reached at times. Such conditions must have been present in HMS Glatton, as exactly similar circumstances were involved.

Experiments were carried out in HMS Gorgon with a view to investigating the temperature in different parts of the magazine, and also in different positions in the cork lagging. For this purpose the bulkhead was repainted and the wood lining was replaced, the space between it and the bulkhead having been filled in with granulated cork. Thermometers were placed between the cases, which contained dummy charges, and also in the cork lagging. The magazine was closed for 68 hours, and clinker and ash ere deliberately kept in the pocket against the bulkhead throughout the trial. The temperatures recorded in the different positions in the magazine averaged 65º Fahr. (without the cooling machinery being at work). In the cork lagging close to but not touching the bulkhead, the average temperature was 70º Fahr. The highest reading was 121º Fahr. opposite the centre of the heap of clinker and ash on the other side of the bulkhead. Some of the cork lagging was removed and samples were sent to Woolwich for analysis. ON removing the wood lining the paint, when inspected, was found to be blackened and blistered.

This experiment was repeated under the same conditions, but without the cork lagging being in place. the temperatures were read after 48 hours without the magazine cooling machinery running. These machines were run for the last 24 hours of the trials, and the temperatures were again read. In general the temperatures in the magazine were somewhat higher than in the first experiment, and in the position where the reading of 121º Fahr. was obtained in the first experiment the temperature observed at the end of the 48 hours, and before the magazine cooling machinery was started, was 150º Fahr. When the cooling machinery was worked, the temperatures in the magazine were very substantially reduced, but the temperatures within the lining rose. In particular the thermometer which had given the reading of 150º gave 200º Fahr., and another some 2 feet above it rose from 108º to 123º Fahr. This rise in temperature, considered in conjunction with a similar observation in the trial with the cork lagging in place, demonstrated that the temperature inside the lagging was governed by the length of time during which the source of heat in the stokehold was applied to the bulkhead, and that it rose considerably, notwithstanding that the cooling machinery was working. After the lining had been removed the paint on the bulkhead was again observed to be blackened and blistered.

An experiment was also carried out with a replica of the bulkhead and lining built up on shore - the cork insulation being saturated with oil fuel. This was a possible, though unlikely, contingency in HMS Glatton. A fire was built up of coal on the "stokehold" side of the bulkhead. No ignition of the cork or the lining occurred, although the conditions were sever; but it was found on applying air pressure that an inflammable gas was blown through into the magazine side which could be lit and put out like an ordinary gas jet. There was nothing to show that a leak of oil had occurred into the cork lagging in HMS Glatton, but the oil tanks were immediately under the magazine, and in the light of the result of the investigation into the properties of the cork used for insulation, the possibility cannot be entirely ignored.

Examination of samples of the granulated cork which had actually been used for lagging the magazines of HMS Gorgon, which came from the same source as that used in HMS Glatton, showed that this substance was most unsuitable for the purpose. It was found that destructive distillation commenced at temperatures less than 200º C., that parts of the products of distillation were inflammable gases, and that the residue of partial distillation was readily ignited in the presence of air.

From the above results, and taking into consideration the conditions existing in HMS Gorgon, it appeared that the piling of the clinker against the magazine bulkhead in HMS Glatton provided all the conditions necessary for the ultimate ignition of the cordite in her midship 6-inch magazine, if there was sufficient access of air to the lagging. If the existence of a hole such as would be left by the omission of a bolt or rivet and a plus pressure in the boiler room be assumed, the opportunity for such access of air in sufficient volume existed. The conclusion was therefore arrived at that the slow combustion of the cork lagging of the magazine led to the ignition of the wood lining and then of the cordite and thus caused the explosion.

In the course of the inquiry into the loss of the ship it was revealed that in many respects the Naval Magazine Regulations had not been complied with. Owing to the short time the ship had been in commission and the very full programme of storing, completion, trials and movements which had been carried out, the routine of inspections laid down had not been organised. This was unfortunate, because if a daily inspection of the 6-inch midship magazine had been carried out, it is possible that abnormal conditions in the magazine might have been noticed and the disaster might have been averted. It is known, however, that the magazine was not entered for some days prior to the explosion.

This disaster provided a very useful lesson regarding the necessity of having access from the weather deck to the upper positions for flooding the magazines. In this ship these positions were inside the after superstructure and were, therefore, inaccessible after the explosion. Had it been possible to flood the after 9.2-inch and 6-inch magazines, it would not have been necessary to torpedo the ship, and she would probably have been afloat after the fire had burnt out.

97. Comparison of Losses by Explosion. - During the war, explosions leading to the total loss of no fewer than five capital ships of the Allies occurred. These are:-

Italy. - The battleships Benedetto Brin and Leonardo-di-Vinci.

Japan. - The battleship Kawachi and the battle cruiser Tsukuba.

Russia. - The battleship Imperatritza Maria.

A cordite explosion also occurred on board the Chilian ship Capitan Prat, which, however, did not lead to the loss of the ship.

The full details of the inquires into the losses of these vessels are not known, but such information as is available is here given in order that these losses may be compared with the four which have occurred in the British Service during the same period.

98. Italy. - On September 27, 1915, the battleship Benedetto Brin was lying in Brindisi harbour when an explosion of ammunition occurred and a fire broke out. The explosion was in the after magazine, and although the ship was severely damaged, she did not sink. She was, however, reported to have been rendered useless, because the whole of the internal fittings in the after part had been burnt out. The engine rooms and masts were destroyed and the bottom of the ship was also badly damaged in several places. The number of casualties was large, and included Admiral Rubin del Cervin, whose flag the ship was flying at the time.

First reports stated that an enemy submarine had penetrated the harbour and torpedoed the ship, but this was proved to have been untrue. The Italian Naval authorities absolutely excluded any question of the disaster being due to enemy action. In the Italian press it was stated that there was no question of foul play, that this was absolutely out of the question, that the vessel was not torpedoed, and that "it was merely a case of an unfortunate accident."

The cause of the fire, which apparently preceded the explosion, has not been discovered, or if it has, the details have never been published. A Press statement attributes the cause of the explosion to a short-circuit in some electrical installation, but this must be taken as a guess at the possible cause, since it has not been confirmed.

From all information that can be gleaned, however, it appears possible to advance the theory that a fire occurred from some unknown cause, and that this fire could not be got under control nor could the magazines be flooded before it reached one of the after magazines and practically destroyed the ship.

On August 2, 1916, the battleship Leonardo-di-Vinci was lying in harbour when, at 11.15 p.m., a fire was observed abaft the mainmast. About a minute later an explosion took place in the after part of the ship, and the whole ship abaft the mainmast caught fire. The ship commenced to sink by the stern and heeled over to port. At 11.40 p.m., after the fire had been burning fiercely for 20 minutes, accompanied by minor explosions, a further explosion occurred and the ship heeled over quickly and sank stern first. She was in only 7 ½ fathoms of water and she appears to have touched the bottom with a list, and heeling over further the water came in through the open scuttles. She then turned over, buried herself in the mud and remained bottom up, inclined at about 10º to the vertical.

Most of the officers were killed outright by the first explosion, but the captain and second in command escaped with severe burns. In all 275 men were lost.

It was afterwards discovered that a quantity of benzene, which was usually kept on deck in tins, had been taken below on account of fear of an air raid. One of these tins leaked and the benzine caught fire, setting the rest alight and eventually causing a serious fire. The flooding of the magazines was begun at once, and was almost completed when the heat of the surrounding plates caused the top layer of ammunition - which was not yet flooded - to explode, making a hole over 20 feet long just under the armour. This caused the ship, which was already resting on the bottom aft, to take a heavy list and the open scuttles completed her destruction.

The primary reason for the loss of this ship is clear, and points to the necessity of adequate fire appliances and a quick method of flooding the magazines and drenching the ammunition while flooding is going on. In the Leonardo-di-Vinci the flooding was not completed in 20 minutes. If she had been fitted with spraying arrangements in her magazines, it is probable that she would not have become a total loss.

99. Japan. - On January 14, 1917, the battle cruiser Tsukuba blew up in Yokosuha [editor's note: Yokosuha here in the original; Yokosuka in the original table at the start of the chapter] harbour and sank immediately. She was, at the time, attached to the Gunnery School, and it was officially stated that the explosion was due to combustion of cordite. But the final report of the Commission of Inquiry has not yet been published.

On July 1, 1918, the battleship Kawachi blew up in Takuyama bay. The explosion took place on the starboard side forward, and the ship capsized and sank in three minutes, resting on the bottom with the port side of the bridge showing above water. The loss of life was 621 officers and men. A Committee of Inquiry has decided that the explosion was due to the spontaneous combustion of cordite, but no full report on the subject has yet been received.

Further statements on the subject of the loss of these two ships have been made by the Minister of Marine and other authorities. Extracts from these statements are given below, but they must be read with reserve.

In February, 1919, the Minister of Marine, speaking in the Upper House, stated that Inquiry Committees were appointed to inquire into both the Tsukuba and Kawachi disasters. In the former case some persons were found to be more or less careless and were punished accordingly. In the latter case inquiries were still being held, and, so far, no negligence on the part of any officer or man had been detected. He expressed the opinion that there was nothing wrong with the magazines, but that it was considered necessary to improve the cases in which the cordite was stowed.

In the House of Representatives in the same month, in speaking on the Naval Estimates, the Minister of Marine referred to the fact that magazine cooling machinery, the establishment of which had been approved some time ago, was still in use, but that money was required to instal "another apparatus" in addition. At present several charges are stowed in a rectangular case, but in future only once charge is to be stowed in a cylindrical case. He explained that although the latter method occupies a bigger space, yet the consideration of space must be subservient to the safety of the vessel. He also referred to the invention of a "safety mixture" which increased the life of cordite, and stated that all cordite more than six years old was to be withdrawn.

This indicates at least an atmosphere of uneasiness as regards the safety of the magazines and the cordite, but the following reply given by the same Minister a fortnight later adoopts rather a different line:- The reply is "With regard to the Tsukuba disaster, we found, on inquiry, that the captain and the gunnery officer of the warship were a little careless about the handling of the key of the magazine, and they were punished accordingly. Just before the explosion took place the key which is generally kept in a box in the captain's cabin, had been left in the officers' ward room for a little while, and it is suspected that during this short interval somebody had fooled with it. Although very careful investigations were carried out the authorities could not find any evidence of a scheme of mischief."

As a result of political pressure an official statement on the Tsukuba disaster has been published, and the following extract is of interest as expressing the views of a senior Japanese naval officer:-

"In spite of our painstaking investigations we could not find any trace of spontaneous combustion of cordite. On the other hand, we made certain discoveries which, though insufficient as evidence, led us to suspect the blowing up of the warship was due to artificial agency. The first factor of suspicion is in connection with the key of the magazine. It is scarcely necessary to say that this key is one of the most important things belonging to a warship, and is always kept in safe custody in the captain's cabin. On the occasion of the Tsukuba disaster this key was not kept in the place where it should be - it was found at a place quite different from the captain's cabin. Whether the gunnery officer, in whose charge the key was always left, had forgotten to stow it away, or whether it was taken out of the box in which it was always kept, is impossible to find out, because of the death of the gunnery officer, who went down with the ship. Anyhow, the discovery of the key at a place quite different to where it should be is enough to arouse one's suspicion.

"Another factor of suspicion which might possibly have been the cause of the explosion was the presence of certain malcontents amongst the crew of the warship. One petty officer and two seamen were suspected, but they have all fallen victims to the explosion and only their bodies were discovered, which of course give us no clue to the cause of the disaster. The petty officer was ostracised by his comrades and was brooding over it. One of the seamen was being severely examined on an alleged charge of theft, and presumably he sought self-destruction out of despair. Another seaman was a drunkard and often threatened to do something atrocious. Very strict investigations have been carried out about he behaviour of these men, but no evidence could be obtained.

"The cordite stowed on board the Tsukuba at the time of the disaster was manufactured at the explosives factory at Hiratsuka, which is under the supervision of Englishmen; the cordite stowed on board the Kawachi was also manufactured by the same factory. Cordite is generally put to the severest test before it is shipped on board and therefore there could be no mistake. The said factory will be turned over to the Imperial Navy on April 1, 1919, and thenceforth it will be run under the direct supervision of the naval authorities, but this on no account means that the authorities regard the management of the factory by private individuals as dangerous.

"If we grow too nervous of spontaneous combustion and make cordite of insufficient explosive power, it will seriously affect our fighting power, and it is essential to exercise great vigilance to prevent plots. Since the magazines are thrown open when carrying out battle practice, if there by any man amongst the crew who is likely to dare to commit a heinous crime, the carrying out of battle firing is extremely dangerous and therefore it must be given up altogether. One way of solving this difficult problem is the improvement of the magazine with the object of minimising the effect of explosion. For this reason the magazines of all new warships as well as those of the ships of the Kurama class have been greatly improved, so that in the future, even when explosion of cordite takes place again, only a part of the magazine will be destroyed. Never again shall the ship sunk with hundreds of lives on board. Although the Tsukuba inquiry was closed, the naval authorities are still carrying out all sorts of investigations."

The above statement displays a curious mixture of ideas, and if it is read in conjunction with the preceding statements it seems that the Japanese authorities gravely suspect their cordite and their system of magazine stowage, but would like to be able to put the loss of the two ships down to sabotage. The evidence of this sabotage appears to be very small, and is made the most of. The system of stowing cordite in bulk in rectangular cases was abandoned by the British Service in 1910, and the Japanese are apparently now following our example. The proposed improvements in magazines probably consist of supplying weakened cases and fitting spraying and drenching arrangements, and they are learning from us all there is to learn about modern methods of manufacturing cordite and will no doubt apply this knowledge in their own country.

100. Russia. - On October 20, 1916, at about 6.10 a.m., a fire was reported in one of the forward 5-inch magazines of the battleship Imperatritza Maria, and at 6.15 a.m. there was a violent explosion. The fore part of the ship was much shaken, but the fore turret was seen to be still intact, through the flames. At about 6.30 a.m. a second violent explosion occurred and the foremast and funnel were destroyed. The vessel remained on an even keel and the after magazines were all flooded. The electric light failed after the second explosion. At 6.45 a.m. the vessel was a little down by the head and an attempt was made to tow her into shallow water. Two salvage tugs came alongside, one on either side, and attempted to pump water on to the fire, but this was of little avail. At 7.0 a.m., while the stern of the ship was being towed up into the wind so as to blow the fire forward, a third violent explosion occurred in one of the port forward 5-inch magazines and the ship started to sink by the head, turning over to port. Between the second and third heavy explosions small reports, 26 in number, were heard as though individual shells were going off. Vice-Admiral Kolchak, who was on board with his staff, left the ship after the third explosion and all the officers and crew who had not already jumped overboard embarked in the two salvage tugs, which sheared off clear of the ship. The list to port gradually increased and at 7.15 a.m. the ship turned completely over and sank. The bottom of the ship was showing above the water for a day, but gradually disappeared. Salvage operations have been in progress for two years and it is reported that the ship was placed in dock, bottom up, in June 1919. The loss of life was 1 officer and 150 men killed and 240 others severely injured, of whom a large number have since died.

The cause of this explosion is not definitely known. All that is clear is that a fire originated in one of the smaller magazines and eventually spread to other magazines. This points to the fact that if it had been possible to flood the forward magazines quickly the original explosion would not necessarily have caused the loss of the ship.

101. Chile. - On March 11, 1916, an explosion occurred in the after magazines of the Chilean flagship Capitan Prat, the ship being at the time at anchor in Valparaiso. Only two cases of cordite ignited, and the ids of the cases were blown off. Luckily the construction of the ship was such that the explosion had an easy vent through the ammunition hoist to the after 10-inch turret, and through the hatch outside the magazine and into the dynamo room to the upper deck. The 10-inch shell, stored in bags alongside the magazine, behind only a thin partition, were undamaged.

The magazine was fitted with cooling machinery and the temperature taken a few hours before the explosion was 52º F. All the cordite on board the ship had been made in England, and all our tests were carried out in the Chilean Navy, both in magazines ashore and afloat. It was therefor possible to trace the antecedents of all the cordite in the magazine concerned, and to examine the records of all the heat tests carried out with it. It was found that the Mark I. cordite in the magazine which had ignited was from 17 to 20 years old, and that heat tests as low as 3 ½ minutes had occurred as far back as December 1914. This cordite was therefore approaching the end of its life and would in the British Service have been withdrawn and destroyed long ago. There was no possibility of tracing the exact date of manufacture or the maker's name of the two "Chilean lots" of cordite concerned, but it was known to have been supplied between 1898 and 1902, at the time when there was a possibility of its having been made up from re-worked materials, or even of cordite rejected for failure to comply with the British stability tests. In these circumstances spontaneous ignition of cordite is by no means unlikely, and there is little doubt that this is what occurred. This fact, however, does not constitute the interesting part of the accident, but the result is a very good example of the efficiency of the various steps which have recently been taken in the British Service to ensure venting of cases and an adequate vent from the magazine to the weather deck in case of an explosion in the magazine.

One of the cases - containing a reduced charge of Mark I. cordite - fired, blowing open the hinged lid of the Canet pattern powder case, which, luckily, had not been properly fastened. This formed an easy vent for the explosion, but the flame ignited the cordite in two cases - in opposite and higher divisions - which contained three full charges of M.D. cordite. Although these cases had the lids secured, the flame found entry through the defective rubber sealing rings. This demonstrated the importance of having cases which are flashtight as well as possessing satisfactory venting qualities. The contents of three cases in the magazine thus exploded; but, owing to the ready vent provided by the construction of the ship, the gases escaped before sufficient pressure was generated to damage the remainder of the contents of the magazine, and the ship was thus saved.

 Return to WWI The Maritime War

 Return to WWI Archive main page.