SOO Histoi^y of Cliefrikal Discovenes. 
of heat, and then forms a new acid^ to which he has given the 
name of the nitro-saCcliaric. This acid is very soluble, and 
crystallises with great facility in fine colourless prisms, tran- 
sparentj flat, and striated like those of sulphate of soda. Its 
taste is acid ; it is slightly saccharine, and very like tartaric 
acid. It produces no change in metallic or earthy solutions. 
United to potash, it forms a super-salt and a neutral salt, both 
of which crystallise in fine needles, which have a sort of ni- 
trous taste. It detonates like nitre on burning coals. The 
new acid dissolves carbonate of lime with a strong eflervescjence, 
and the solution yields fine prismatic needles. This salt does 
not attract humidity, and is scarcely soluble in concentrated al- 
cohol. Thrown on burning coals, it melts in its water of cry- 
stallisation, and then detonates like nitre. With oxide of cop 
per, the nitro-saccharic acid forms a crystallisable salt unalter- 
able in the air ; — with magnesia a deliquescent uncry stallisable 
salt ; and with oxide of lead an uncry stallisable salt, unalterable 
in the air, and resembling gum. It dissolves iron and zinc, 
with the disengagement of hydrogen gas, the results of which 
are uncrystallisable combinations. 
3. That zvool^ and particularly the muscular fibre (Jibrine,) 
when treated with sulphuric acid, yield a particular white pul- 
verulent substance, which he has called Leucine. When a so- 
lution of leucine, in lukewarm water, is evaporated spontane- 
ously, a number of small isolated crystals are formed at its sur- 
face. They are flat, perfectly circular, and have exactly the 
shape of the moulds of buttons, with a rim round their circum- 
ference, and a point or a depression in their centre. Leucine 
has the taste of the juice of meat. It appears to be specifically 
lighter than water. It melts at a temperature considerably 
above that of boiling water, and spreads an odour of putrid 
meat, subliming partly in the form of small white insulated 
crystals. Leucine dissolves easily in nitric acid, and produces 
fine colourless and divergent needle crystals, which are a' new 
acid^ analogous , to the nitro-saccharic. This nitrodeucic acid 
forms, with salifiable bases, salts which have quite a different ar- 
rangement from the nitro-saccharates. Combined with lime it 
yields a salt, which crystallises in small rounded groupes, and 
is unalterable in the air. Thrown on a burning coal, it fuses 
3 
