SCIENTIFIC SUMMARY. 
103 
observed that the derivation of the new body from nitric acid was perfectly 
analogous to that of aniline from nitrobenzol. 
Nitrobenzol. 
C 6 H 5 N0 3 
Nitric acid. 
H0,N0 3 
Aniline. 
C 6 H 5 M 2 
Hydorylamine. 
ho,nh 3 
"The new body might be looked upon as ammonia, in which one atom of 
hydrogen is displaced by what might be called the residue of water, the 
atomic group HO, which by some had been called hydroxyl, by others 
hydoryL 
Ammonia. Hydorylamine. 
H ) 
HO 
H VN 
H 
H) 
H 
It was certainly interesting to see the simplest of reactions, familiar to every 
chemist, still yielding a harvest of such splendid results. 
Action of Potassium on Gun-cotton. — Some curious facts relating to the 
action of the alkaline metals on gun-cotton have been pointed out by Mr. 
W. S. Scott. In some of his recent experiments he accidentally dropped 
a piece of potassium upon some gun-cotton lying upon his laboratory table, 
and was surprised to see that the gun-cotton immediately exploded. He then 
instituted a series of researches to determine what conditions were necessary 
for the explosion to take place — whether the phenomenon was the result of 
moisture ; whether other metals would act similarly ; &c. He found that, 
notwithstanding all his precautions to prevent friction, the gun-cotton still 
exploded. When sodium was employed, a like result followed, though the 
gun-cotton had been rendered perfectly anhydrous. When an amalgam of 
sodium and potassium was used, no apparent result was produced. Various 
other metals were experimented with, but decided effects were obtained 
only with the metals of the alkalies. One of Mr. Scott’s discoveries is the 
fact that when metallic arsenic is mixed with gun-cotton, a blow of the 
hammer is sufficient to ignite it. 
GEOLOGY AND P ALiEON OTLOGY. 
The Fossils of the Hoyle’s Mouth Cavern. — In a letter to the Geological 
Magazine , Mr. H. H. Winwood describes his explorations of the “ Hoyle’s 
Mouth Cave,” near Tenby. In one of the furthest chambers from the 
entrance, he found, beneath a mass of undisturbed breccia, the right 
and left thigh-bones, the hip-bone, some vertebrae, and other relics of 
the great cave-bear : these were extracted in a very perfect state. Near 
them were the radius of Hycena spelcea, and several loose bones and teeth of 
the fox, deer, and ox. In one of the passages leading from this chamber he 
discovered fragments of bones and an incisor of the hyaena ; also, in the breccia 
