Concussion fuses and spherical shells in the XIXth century.

That’s an interesting question since the answer, at first, should be rather straightforward. After giving some thought to the question and going through a few books, I could summarize my answer in the following way. There are some references in older works, beginning in the XVIIth century, as to the existence and/or experiences relative to concussion (impact) type fuses. But it is clear that their usage was at most confidential until the introduction of the rifled artillery, the time fuse saw a universal usage since it was easy to manufacture and to use. Introduction of rifled artillery and more modern artillery projectiles permitted an easier approach using the inertial principles.

Looking at older books (essentially middle and late XIXth century ones), it seems that essentially two approaches were tested on spherical shells and based on fuses whose type in French is "Fusées percutantes sans composition fulminante" (Translation: Concussion fuse without fulminate composition):

_ Using the properties of certain chemicals as sulfuric acid, ammonium chlorate (translation of Chlorate de potasse ?),... On impact, combining such chemicals should produce an incendiary composition.

_ Using the property of the plaster to give away under impact (used by Springlard) or the molten zinc witch became brittle (?) at a temperature of 150°. In each case it was used to separate the shell in two segments, one with the military charge, the other with a slow burning mixture inflamed at the shell departure.

_ The Belgian artillery major Springlard worked as soon as 1850 on a functional impact fuse (see fig. 1) but it seems not to be designed for spherical shells but for the more modern ogival shells. The Swiss colonel Pictet soon followed him in 1858 (same principles) whose fuse was introduced in Austrian service under the denomination of Concussionsbrandröhren (fig. 2).

In France, trials were conducted between 1860 and 1870 but mostly for use in rifled artillery (system La Hitte). Until 1860, the spherical shells used a wooden fuse with one predetermined time setting (Ecole de Pyrotechnie) or, for the shrapnel type shells, a wooden fuse with three predetermined time settings (by Captain Maucourant and the Ecole de Pyrotechnie). The impact fuses, which were given some attention and eventually taken in the French army service, were of the Desmaret and Maucorant types (the same man but a different fuse design of course). Other trialsFlorentin and Cavalié made other trials.