294. Dr. H. Will on M. Reiset’s Remarks 
riments further, he found that many non-nitrogenous organic 
bodies, as also many metals, presented this phenomenon, as 
for instance, iron, zinc, tin, lead, arsenic, and also copper. 
He obtained, for example, a very perceptible quantity of am- 
monia with woody fibre, oxalate of potash, oxalate of lime, tar- 
trate of lead, acetate of lime and asphaltum; with acetate of 
potash, acetate and tartrate of lead, tartrate and benzoate of 
potash, oxalate of lead, sugar, wax, olive oil and naphthaline, 
very little; and with resin, alcohol, ether and olefiant gas, 
none whatever. The quantity of ammonia agreed in a re- 
markable manner with the quantity of hydrate of potash used 
in the experiment. He further observed, that perfectly pure 
hydrate of potash, evaporated so far that it ceased to give off 
water, when heated alone yielded no ammonia, but that it ac- 
quired this property when exposed to the air for some time. 
He observed exactly the same with caustic lime and hydrate 
of lime, and also with fresh prepared potash-ley allowed to 
stand for twenty-four hours. 
Faraday further obtained ammonia when he heated a strip 
of well-purified zinc with hydrate of potash made from 
potassium, in a carefully prepared atmosphere of hydrogen ; 
but could discover no ammonia when he heated the zine with 
hydrate of potash which had been previously kept in a state 
of fusion until it ceased to give off water. He _ states, 
moreover, that the ammonia was generally observed before 
the disengagement of the hydrogen by the decomposition of 
the substance employed commenced. 
Tartrate of lead ignited with potash and the cold residue 
brought in contact with a drop of water, evolved ammonia. 
White clay from Cornwall, which after being strongly ig- 
nited was exposed to the air for eight days, yielded much am- 
monia, while another exactly similar portion of the same clay, 
which after ignition was preserved in a well-stoppered bottle, 
gave no ammonia. 
Pure sea sand, heated to bright redness in a crucible and 
cooled on a plate of copper, gave no trace of ammonia, although 
it was very readily observed when the hot sand previous to its 
being heated was held for some moments in the hand and 
stirred about with the finger. 
These experiments evidently agree with the observations of 
Braconnot*, who states that many porous minerals, such as trap 
from Chaume de Tendon, eurite, some species of granite, ser- 
pentine from the Vosges, amphibole, muschelkalk, &c., by dis- 
tillation in a glass retort, yielded an ammoniacal product. 
* Annales de Chimie et de Physique, t. \xvii. p. 104. 
