Analytical Chemistry. 117 
acid is added, and then a little nitrate, until all the solution of the nitrate 
with the washings is poured in, and about one-fourth of the acid is left... 
Care should be taken that, for the first hour, the effervescence is slow. 
hen the whole of the solution of the nitrate is poured in, the remainder 
of the acid must be added from time to time, and the whois left until 
effervescence ceases. The liquid is then carefully separated from 
undissolved zinc, which is well washed with the smallest quantity of water, 
and the whole distilled with hydrate of lime, the ammonia being col- 
lected in a proper condenser. The great danger to be avoided consists 
in allowing the hydrogen to be liberated too rapidly, by means of which 
so much heat is generated as to cause a portion of the nitrogen to esca 
as binoxyd of nitrogen.” Nesbit estimated the ammonia by a volumetric 
method. He gives the results of sixteen determinations of nitric acid, by 
five different operators, in nitre both pure and mixed with 6 to 9 times its 
weight of common salt, and in the nitrates of baryta sot a In each 
case, the accuracy of the estimation left nothing to be d 
Nesbit’s method has been employed in this laboratory with satisfaction, 
though several trials were requisite for learning the precise method o 
procedure, 
e have thus noticed the method of Nesbit, because it has not, to 
our koomledge, been described in any treatise on chemical analysis, and 
ecause, since its publication, others have — — based on the 
same principle which are more or less worth 
Several years after the method of Nesbit was pubis, Martin gave 
out the same A tase as original, Comptes Rendus, xxxvii, 947, with this 
ect the accuracy of ne sige, though in presence of gelatine the 
reduction proceeds very sl 
In 1861, Schulze, of Rostock, proposed to convert nitric acid into am- 
monia by the action of sodium-amnalgam or of platinized zinc in e 
of excess of alkali (Chem. Centralblatt, 1861, pp. 657 and 833). The 
manipulations described by Schulze for — peepee results are some- 
Iff, often practical, 
by Kno nop and himself, in which the nitrogen of the ammonia is liberated 
by a —— of hypochlorite of soda and bromine, and estimated by 
measurement. 
e ‘tals of nitrates by reduction with a mixture of zinc and iron in 
alkaline liq uid has also been the subject of nearly cotemporary study 
* 
