RESIN OF TURPENTINE. SJ) I 



soluble in cold alcohol, but not precipitated by the acetate of 

 copper. 



The white resin, galipot, derived from the pinus maritima, 

 consists almost entirely of a colourless, crystallizable resin, 

 named pimaric acid, C 40 H 30 O 4 , of the same composition as the 

 preceding resins, but differing from them in properties. When 

 the crystallized resin is dissolved in alcohol, it soon separates 

 as an amorphous powder, which is much less soluble, without 

 alteration in composition. When distilled in vacuo, pimaric 

 acid is converted into another resin, pyromaric acid. Boiled for 

 a long time with nitric acid, pimaric acid gives rise to a new 

 acid, containing nitrogen, azomaric acid, C 40 H 18 O 12 N + 4HO, 

 of which the capacity of saturation is double that of pimaric 

 acid. (Laurent, An. de Chim. Ixxii, 383). 



By the dry distillation of colophony, M. Fremy obtained a 

 heavy light- coloured oil, almost destitute of taste and smell, 

 boiling above 482, which he named resinein. Its composition 

 is expressed by C 20 H 15 O ; and it appears to be formed by the 

 abstraction of an atom of water from half an equivalent of 

 colophony. By distilling purified resin with eight times its 

 weight of slaked lime, the same chemist procured two liquid 

 products, resinone C 10 H 9 O, soluble in alcohol, and boiling at 

 172.5; and resineone C 23 H 18 O, less soluble in alcohol, and 

 boiling at 2.98. 5 (Liebig, Annalen, xv, 282). 



By distilling resin at a higher temperature. MM. Pelletier 

 and Walter obtained a liquid, retinaphtha C 7 H 4 ; which gives 

 with chlorine a compound C 14 H 6 C1 2 , At the same time with 

 retinaphtha, a less volatile liquid, retinyle, C 9 H 6 , is formed. 

 The less volatile product of the distillation of resin affords a 

 liquid retinole, C 8 H 4 , with a solid compound retisterene or meta- 

 naphthaline, which is isomeric with naphthaline. (Ann. de Chim. 

 &c. Ixvii, 269). 



Common resin is converted into shoemaker's resin, or Bur- 

 gundy pitch, by heating it repeatedly with water, and going to 

 dryness. 



Oil of lemons, C 10 H 8 . This essence is extracted from the 

 rind of the lemon (Citrus medico], usually by expression. The 

 crude oil is pale yellow, but when rectified it is colourless, has 

 a strong smell of lemons, density 0.847 ; and boiling point 



