The daily morning journal and courier., 1898-03-12
FACTS ABOUT GUN-COTT0N
THE SAFEST OF THE HIGH EXPLO-
 SIZES FOR NAVAL WARFARE.

Il '~N"NN Ne-~
 Way In Which 1t Is Made Detonati on or | Explosion by Shock.
 Gun -cotton" said an ordnance of- | ficer a few days ago, when asked
 about the qualities of this substance which is used in the torpedoes carried
 by the ships of the navy, lis by far the safest of any of the high explosives, That is the reason it Is chosen instead
 of the nitro-g -glycerine preparations,
 which, although they will produce
 more powerful effects. are very danger
 ous things to have on shipboard. They
 can be exploded too easily, by the ap-
 plication of heat by shock, and, un- der some conditions, by spontaneous
 combustion. But the gun cotton, as long as 1t Is kept wet, is absolutely safe, and there is no trouble about pre- serving the necessary degree of mois- ture"
 Precisely the same opinion regarding gun-cotton as an explosive for naval
 warfare was expressed by the superin-
 tendent of one of the largest powder l manufacturing firms, a man who has
 had much experience in the making of
 gun-powder and gun-cotton.
 Not only is gun-cotton absolutely inert and harmless so long as it is wet" he said, but it does not neces- o...Jx
 when dry. Of course 1t Is then much
 more liable to do so, but if it is undis-
 turbed in any way a considerable quantity of it might remain dry with
 out any accident. In our works we are extremely careful about the way in
 which we handle dry gun-cotton, but
 there is no need of any precautions
 when it is wet. On shipboard the disks
 of dry cotton which are used as prim-
 CTS to detonate the wet are always
 kept away from the magazine, either on deck or in one of the cabins. The
 only danger from them would be in
 case they were dropped while being
 handled. The result then would not always-perhaps not usually-be an ex-
 plosion, but you never can tell with
 certainty. One of the disks might be
 dropped half a dozen times and not ex- plode, and the next time, under appa-
 rently the same conditions, it would go
 off As far as heat is concerned, if the
 dry gun-cotton is exposed to contn-
 ued high temperature for long time, it is likely to decompose, undergoing
 chemical changes which generate heat
 and may go far enough to cause spon- taneous combustion. But no such con- dition is possible on a ship, because the gun-cotton is always carried in the torpedo heads and inspected regularly to see that it remains wet. The heads
 are practically alright but if any evaporation is noticed the cotton can be dampened again by a regular means
 arranged for that purpose"
 The process by which so common and harmless a substance as cotton Is con- verted into a high explosive is com paratively simple one. Pure raw cot ton or ordinary cotton waste is steeped
 in solution of one part of nitric acid
 and three parts of sulphuric acid. The
 nitric acid is the one which renders the
 cotton explosive, the presence of the
 sulphuric being required only to absorb llt WdleI, lHuS dllOWlIS lIlc DlItT dClQ
 to combine more readily with the near ly pure celluIose of which cotton con sists. After the cotton has soaked in the acids for several hours. it is taken from the pots and squeezed through heavy rollers to extract all the super
 f1uous acid which 1t has not absorbed
 Then it is washed carefully and thor
 oughly still with the same object of re- moving the free acid. If any of this remained it's tendency would be to cause chemical changes in the gun-cot- ton and decompose 1t. Formerly this
 washing was the last process resorted
 to for the removal of the free acid, but
 few years ago Sir Frederick Abel found that the cells in the cotton fibre
 so absorbed and, retained the acid by
 capillary attraction that the washing
 failed to extract 1t entirely. To reme-
 dy this and make the gun-cotton more
 pure, it is now, after being washed,
 passed through machine similar to
 that which grinds up the rags In a pa-
 per-mill. Here 1t is crushed thoroughly and afterward washed again until the last trace of free acid disappears, and the cotton comes out in the form of a
 sort, white pulp, closely resembling the pulp of which paper Is made. This concludes the process of actual manu- facture and it now remains only to convert the gun cotton into the most convenient form for the use to which it is to be put. If 1t is to be employed in making powder, 1t is dried and
 stored away in pulverized form, but if it is designed for filling torpedoes it
 must be compressed to a certain den-
 sity and moulded into the shapes which will best enable it to be packed into the torpedo heads These shapes vary according to the design of the tor
 pedoes and the method of packing. Sometimes they are disks and some times cylinders, flat squares or cubes. If uncompresed and dry, the gun-cot- ton would be extremely light, weighing no more than ordinary cotton batting,
 but when made into the above forms it
 is compressed to the density of about
 one, or, in other words, to the density
 of an equal amount of water. The per-
 centage of moisture remaining in the
 gun cotton when it Is packed into tor pedoes varies between fifteen and thir- ty. So safe from explosion, unless de- tonated, is a brick of wet un-cotton that 1t may be placed upon hot coals.
 AS the moisture dries off from the out