s 
Determination of Mitrogen in Organic Compounds. 259 
composing the chloride of platinum and ammonia by heat. They 
therefore recommend that the spongy platinum used to form the 
chloride, should be well washed with hot distilled water, before 
being dissolved in the nitro-hydrochloric acid. ' 
“If we weigh the nitrogen as the chloride of platinum and 
ammonia, we have one hundred and seventy seven parts of it for 
every two thousand seven hundred and eighty eight of the double 
chloride, but if as metallic platinum, one hundred and seventy 
seven parts for every twelve hundred and thirty three of the 
metal.” it: Milas, 
“'The weight of the chloride of platinum and ammonia remains 
constant under a long continued drying at 212° Fah., as well as 
that of the filter, after it has been completely washed.. If there 
be a trace of acid remaining on the filter it becomes dark .and 
friable.” 
I believe that now all the important steps in this operation have 
been fully detailed, and I shall conclude with a translation of a 
letter of Prof. Liebig’s, that was attached to the original publica- 
tion, in order that it may be seen, how highly this new method of 
estimating the quantity of nitrogen in organic bodies is esteemed 
by that distinguished chemist. 
_“T have had the pleasure of being constantly present at the 
development of the experiments by which Drs, ¥V. and W. by 
degrees have arrived at the method, which they have here de- 
scribed, I regard this new method of estimating nitrogen as one 
of the most important improvements in organic analysis, because 
it determines the quantity of nitrogen with a certainty and pre- 
qsion which until now were wanting, The whole opreation is 
completed in a few hours, and with all the accuracy of the deter- 
mination of the carbonic acid. Idoubt not that this apparatus 
will very soon replace the ordinary method, to the contentment. 
of all analytical chemists.—J. L.” . 
The little experience and observation I have had of it, verify 
the opinion of Prof. Liebig, and in simplicity it is every thing 
that can be desired. 
Geissen, November, 1841. 
