63 



XVII. THE OCCURRENCE OF GUAIOL IN THE TIMBERS OF 



CALLITRIS SPECIES. 



The odour given by the wood of the CaUitris generally, with perhaps the 

 exception of C. Madeayana, is quite pleasant, somewhat aromatic, and character- 

 istic. It is distinct from that of any other timber known to us, and the wood 

 of Tetraclinis qiiadrivalvis from North Africa, has a different odour.* 



To obtain the volatile constituents, the ordinary methods of steam distilla- 

 tion were employed. The log was cut into planks, and these were then run 

 through the planing machine, and the shavings thus obtained were utilised for 

 the purpose. The substances which distilled, separated upon the surface of the 

 condensed water in a semi-solid mass, and were easily skimmed off. The 

 material had a marked odour of the Australian " Cypress Pine " wood itself. This 

 odour is given by the liquid portion of the product, as shown in the previous 

 article, and when the solid substance was obtained pure, it was practically 

 odourless. 



The distillations in most instances were continued for eight or nine hours, 

 but even then the shavings had a strong odour of the wood, and it is thus evident 

 that more crude material would have been obtained by longer distillation. 



The timber of C. glaitca was taken for the main investigation and four 

 distillations were made, giving a mean yield of 0-82 per cent. The crude semi- 

 solid oily product was squeezed through cloth, by which means the greater 

 portion of the solid was retained. The cake of stearoptene was then placed 

 between drying paper and subjected to pressure in a screw press. A solid hard 

 cake was thus obtained, and this was dissolved in cold go per cent, alcohol, filtered, 

 and allowed to crystallise. TJie crystals which formed were hexagonal prisms, 

 terminated by obtuse rhombohedrons, and some were of considerable size, of a 

 brilliant nature and glistening in appearance. After repeatedly crystallising from 

 alcohol, the material was again dissolved in alcohol, and water added to slight 

 turbidity ; crystallisation then rapidly took place, most of the material separating 

 out in small crystals. This appeared to be a very good method whereby to purify 

 the crystals, as they were thus obtained free from enclosures. The}^ were finally 

 re-crystalhsed from alcohol. 



The facility of crystallisation of this substance may be illustrated by melting 

 it either on water or on mercury, and allowing it to cool slowly; as it cools, a 

 minute trace of the solid is added, when crj^stalline threads shoot out in all 



*]M. Grimal (Compt. rend., 1904, 927) has investigated the steam-distilled oil from the wood of the North 

 African species of Tetraclinis. He records the phenol which it contains as carvacrol, and the crystalline body as 

 thymohydroquinone. 



