1815, On the Analysis of Organic Sulbstances> 271 
move the slide till the numbers representing. the quantities of each 
element coincide. with some multiple of these elements marked on 
the scale; and these multiples, or some submultiple of them,. will 
represent the number of atoms required, Thus we find. when 32-4 
carbon. stands opposite two or four atoms of carbon, 2°8 -hydrogen 
will coincide with one or two atoms of hydrogen, and 64°3 oxygen 
with three or six atoms of oxygen. Of course we adopt the lesser 
numbers, which are the same as those obtained before. 
Example 2.—Suppose we had found the weight of an atom of a 
quaternary principle to be 97-82, and that 97-S2 parts of it con- 
tained 37°65 carbon, 17°52 azote, and consequently 42°65 oxygen 
and. hydrogen: to find the number of atoms of each, we place, as 
before, 10 on the slide opposite oxygen: then opposite 37-65 will 
be found 5 carbon; opposite 17°52, 1 azote; opposite 40, 4 
oxygen ; and opposite 2°65, 2 hydrogen ;* the number of atoms 
required, ; ‘adie 
Or supposing that we had not been able to ascertain the weight of 
a particle of the compound in question, but had found. that 100 
parts of it contained 38°5 carbon, 17-9 azote, and consequently, 
43°6 oxygen and hydrogen: to find the number of atoms of each, 
we proceed just as before, and still find that 35°5 carbon will stand 
opposite five or ten atoms of carbon, when 17-9 azote coincide with 
one or two atoms of azote; + and that 40°9 oxygen will be opposite 
four or eight oxygen ; and 2-7 hydrogen, opposite two or four hy- 
drogen ; which agree with the former results. , 
These examples are doubtless more than sufficient to show how 
this admirable instrument may be made to facilitate and yerify 
analyses, on the practical part of which some observations now re-~ 
main to be made. 
1, The depriving organic substances of water without decom- 
posing them has always constituted a great source of difficulty in 
the prosecution of this department of chemistry. The method 
adopted by Berzelius, and, which is founded. on. the happy applica- 
tion of a well-known principle by Mr. Leslie, is certainly one of the 
best that has been proposed. ‘This cousists in exposing the substance 
* These two numbers make up 42°65, the quantity of oxygen and hydrogen 
present. As no solidsibstance, probably, will befound to contain more than six 
vr even four atoms of hydrogen, it will perhaps be sufficient in practice to divide 
as often as possible the quaytity of oxygen and hydrogen by the weight of a par- 
ticle of oxygen, and to consider the quotient as representing the number of par. 
ticles of oxygen, and the remainder as hydrogen, ‘Thus in the present instance 
oo = 4, with a remainder of 2°65 for hydrogen, and 10 x 4 = 40, the quan- 
tity of oxygen. To prevent ambiguity, however, it. will be better to have re- 
fourse fo experiment, which without any great nicety will enable one to decide 
between one arid eight atoms of hydrogen, as in the above instance between 2:65 
hydrogen and 12°65 hydrogen, 
+ It is extremely probable that azote never enters into a compound more than 
in one, or certainly not more Uran in two, proportions, The knowledge of this 
will facilitate the process, as the quantity of azote found may be at once placed 
Opposite one azote... ‘ 
