M. Gautier giving the proportions of materials, directs—
| Blood in a dry state | 3 parts |
| Nitre | 1 " |
| Iron scales | 150
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 | 150
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 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 cylinder, placed in the sand-bath, and though combustion 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 after 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 complete 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 evaporated to dryness; even now, by applying a piece of red-hot charcoal, it was found that the nitre was in a condition to enter [p486] into active combustion, and if the cylinder had been again charged and subjected to a temperature capable of producing ignition, there cannot be a doubt, but that a similar inflammation would have taken place.
However this might be, this quantity of material was now mixed with hydrate of potash to an equal weight with the nitre used; and the mass subjected to the heat of a sand-bath for some hours, and afterwards submitted to the action of a naked fire for rather more than an hour, and the heat brought up to redness. No considerable action took place, but some particles of the carbonaceous matter were ejected, and produced brilliant scintillations in the fire, so that we may conclude, notwithstanding the presence of so large a quantity of potash, the properties of the nitre were not destroyed.
H. P.
Canal-street, Birmingham.