Chemical Science. 485 



of Potash, as described in this Journal for July, 1827.*— It is 

 stated in the above article, "numerous investigations induced 

 M. Gautier to conclude that when animal matter is calcined alone, 

 it yields but little cyanogen ; that when mixed with potash it gives 

 more ; that the substitution of nitre for potash, and the addition of 

 iron or scales of iron, augmented the production of cyanogen and 

 gave a ferro-prussiate. The following is the process of manufac- 

 ture to which M. Gautier has ultimately arrived," (for which see 

 the Journal, 227.) 



M. Gautier giving the proportions of materials, directs — 



Blood in a dry state .... 3 parts 



Nitre 1 ^ 



Iron scales -J ^ of the blood employed. 



Blood not being at hand, animal muscular fibre was substituted, 

 and the following results were obtained. I am not aware that the 

 dried parts of animal muscular fibre are more inflammable than the 

 coagulated and dried parts of blood : — 



Muscular fibre .... 3 parts 



Nitre 1 „ 



Iron filings 3^ of the undried muscle employed. 



The muscular fibre, nitre and iron filings were beat into a mass, 

 and partially dried by a moderate heat ; they were then returned to 

 the mortar and reduced to a perfectly homogeneous greyish white 

 powder. This was dried and weighed, and appeared to be reduced 

 to nearly equal parts of nitrate of potash and animal fibre. 



The desiccation having been completed by a very moderate heat on 

 a sand bath, will not, as far as I am aware, differ materially from that 

 produced by exposing the mass in " an airy situation to dry," as 

 nitrate of potash undergoes no decomposition by admixture with 

 animal matters at a low temperature. 



When the desiccation was completed, the mixture was charged 

 into an iron cyHnder, placed in the sand-bath, and though combus- 

 tion was not anticipated in this part of the process, yet the mouth 

 of the cylinder was turned towards the wall, lest an accident should 

 occur, (which appeared to me to be more than probable in some stage 

 of the process.) In about two hours aft^er the cylinder had been 

 heated, I was surprised to see its contents ejected with considerable 

 force, in a state of brilliant combustion. Supposing something in the 

 above experiment had been overlooked, and that, if the materials 

 had been longer in contact previously to subjecting them to com- 

 plete desiccation, this inflammation would not have taken place, the 

 experiment was repeated with the following precautions: after the 

 muscular fibre had been subjected to the action of the pestle in 

 combination with the prescribed quantity of nitrate of potash, the 

 mass was boiled with water for some hours, and then gently eva- 

 porated to dryness ; even now, by applying a piece of red-hot 

 charcoal, it was found that the nitre was in a conditiou to enter 



s 207 and 208. 



