84 
MISCELLANY. 
18. 01. sinap. sem. — 35 lbs. gave 11 drs. of oil, and by other experi- 
ments 15 lbs. gave 6 drs. and 50 lbs. gave 31 drs. The greatest product 
was 8 drs. oil from 10 lbs. 
19. 0/. aether, tanacet. — 20 lbs. of the tops gave 1 oz. of oil. 
20. 01. valer. aeth. — 10 lbs. of the root gave 12 drs. oil and 22 lbs. gave 
18^ drs. of oil, spec, grav, .960. 
Records of general science and Central-Blatt. 
Composition of Bitumens. — M. Boussingault has, from his researches, 
been led to the conclusion that the Bitumens should be considered as 
mixtures of two substances, one liquid to which he has given the name of 
petrolene, the other solid which he calls asphaltene. It is the viscid bi- 
tumen of Bechelbornn, department of Bas Rhin, which has been particu- 
larly the object of the researches of M. Boussingault. 
Petrolene. — Is an oily substance, volatile, possessing a bituminous odour, 
of a pale yellow colour, it is composed of hydrogen and carbon only; it boils 
at 280° R. (662 F.)— Its specific gravity is 0.891 at21'=*, it remains liquid 
at 12°, is little soluble in alcohol, and very soluble in ether. It is ob- 
tained by distilling the bitumen of Bechelbornn with water; it passes over 
with the aqueous fluid, upon which it floats. Upon analysis its composi- 
tion is 
Carbon 0.885. 
Hydrogen 0.115. 
1.000. 
The density of its vapour by experiment is 9.415. 
From these results it is seen that petrolene is isomeric with the oils of 
lemon, of turpentine and of copaiba, and that the density of its vapour is 
nearly double that of the vapour of turpentine. By admitting that 4 
volumes of vapour constitute an atom of petrolene, its atomic constitution 
is the following, C so H 8 4. 
Asphaltene. — Is solid, black, brilliant, it softens^by heat, near 300° R, 
but is decomposed before melting. It is composed of 
Carbon 0.753 
Hydrogen 0.099 
Oxygen 0.148 
Which can be represented by the formula Cso He 4 Qe which 
would seem to prove that asphaltene results from the oxidation of pe- 
trolene. It is obtained by submitting the bitumen of Bechelbornn, purified 
by the prolonged action of ether to a temperature from 240 to 250° R. 
The asphaltum of mineralogists has a composition very close upon that 
of asphaltene. Journ. de Fharmacie, 
