116 Scientifie Intelligence. 
3. The density of the vapor of a substance or its equivalent being 
given, as also the elementary composition and point of ebullition, the 
nature of its constituent parts may be determined, provided the com- 
pound does not include components which have not been isolated, and 
whose influence upon the point of ebullition has not been ascertained. 
4. Reciprocally, from the composition, we may deduce—l, the 
equivalent; 2, the density of its vapor; 3, the density in the liquid 
state ; 4, its point of ebullition. 
These several laws are illustrated by numerous examples, and the 
influence of different radicals on the boiling point given. Thus water 
of “ hydratation” (H* O?) raises the point of ebullition of a substance 
-113°5°C. The oxyd of carbon (C? O?), 57°; pees acid (C? O4), 
90° ; formyle (C* H*), 52°; methylene (C? H*)™, 21°; (C2 H#)e, 17°; 
and hydrogen (H*) diminishes the temperature of sbullton S. 
Benzine (C1? H!?) boils at 86°, MitscuErR.icu. 
Retinaphtha (C14 H!%) boils at 108°, Waren. 
Retinaphtha consists of methylene and benzine; the point of ebulli- 
tion should therefore be 21°; and observation gives 22°. 
Ether (C® H?° 0?) boils at 35°7°, Gay Lussac. 
Carbonic ether boils at 125° to 126°, Erriine. 
The point of ebullition, as above given, ought to be 90° greater for 
carbonic ether than for ether, and so it is. 
Oxalic ether (C12 H?° O8) boils at 183° to 184° C., Dumas and 
Bouttay. And as it differs from carbonic ether in the addition of oxyd 
of carbon (C? O?), the point of ebullition should be raised 57° and ob- 
servation gives 57° to 58°. 
To determine the point of edullitions of Tonmanaksdiee (C2 H+)” from 
that of Benzine, that is, from triformyle (C4 H+). —Formyle raises 
the boiling point 52° ; consequently trifermyle will raise it 52x 3156"; 
methylene raises it 21° ; and tetramethylene consequently 21x 4=84". 
The boiling point of benzine is 86°; now if benzine, which 
raises the temperature 156°, has for its boiling point 86°, which is 70° 
less than 156°, then tetramethylene, which raises the temperature 84°, 
will have for its boiling peint 14°, which is 70 less than 84°. M. 
Boucnarpat has obtained a carburet of hydrogen (C8 H18) which 
boils at 14-5°, and he has called it Caoutchéne. This carburet is no other 
than tetramethylene. 
Alcohol=(C* H1? 02), or isahydrate of bielayle (C2 H*)g (H* 0?) ; 
itboils at 78:4°._ The number representing the influence of its compo- 
nt parts is 2 17=34° for bielayle ; and 113°5° for water ; the sum 
ls 147-5°. . Subtracting 78:4°, the boiling point of alcohol, we ob- 
69-1". We find now the boiling point of benzine or triformyle 
ting 69°1° from 3X52—156°, which represents the influ- 
f triformyle. We thus obtain 87° ; observation gives 86°. 
