The heat generated by the union of ammoniacal vapour and chlorine, caused the destruction of the whole apparatus by an instantaneous explosion.
From this time their attempts to form the oil were confined to small phials of the gas, and their trials of its properties were limited to a quantity not greater than a grain of mustard-seed ; but still the results were attended with danger. In attempting to collect the gas produced in its explosion, by heating a very small quantity under water in a curved tube, the tube was shattered with great violence, and the author received a wound in the transparent cornea of one eye, from which he has not yet recovered.
Explosions equally violent were afterwards witnessed by Mr. Chil- dren and Mr. Warburton, even without confinement : when a small globule of the oil was thrown into a glass of rolive oil, oil of turpen- tine, or naphtha, the glass, though strong, was in each instance shi- vered to pieces.
When a globule larger than a grain of mustard-seed was touched under water by phosphorus, the explosion was so violent as to break any glass vessel in which the experiment was made. But when smaller quantities were employed, a gas could be collected which, by the experiments hitherto made, contains no oxygen and no inflam- mable gas.
When thrown into the solutions of phosphorus, in ether, or alco-
hol, it detonates most violently; but neither ether nor alcohol alone exhibit any violence in their action upon it. ' ' In muriatic acid it gives ofi' gas rapidly, and disappears without explosion. Various experiments were also instituted with other sub- stances, as sulphur and resin, among others, but without any remark- able efi‘ects.
From the general tenonr of these experiments, the author thinks it probable that the substance here examined is a compound of azote and chlorine, formed by the decomposition of ammonia; while the hydrogen of the ammonia unites with another portion of chlorine, and forms muriatic acid.
The heat and light produced during the expansion of this oil into gaseous matter, is considered by the author to be without a parallel in our present collection of chemical facts; and the suddenness of the explosion more instantaneous than that of any compound hi- therto known.
This communication includes an application of Cotes’s theorem to conic sections in general; but the application noticed in the title relates to the parabola in particular, and it may be thus enunciated.
If any number of radii vectores S P be drawn from the focus to the curve, making equal angles P S P with each other; and if an equal
