CRYSTALLINE DEPOSIT OCCURRING IN TIMBER. 187 



On the CRYSTALLINE DEPOSIT OCCURRING in the 



TIMBER OF the " COLONIAL BEECH," 



Gmelina Leichhardtii, F.v.M. 



By Henry G. Smith, f.c.s. 



With Plates VIII and IX. 



[Read before the Royal Society of N. S. Wales, November 6, 1912.] 



This Australian tree belongs to the Family Verbenacese, 

 and is thus not a true "beech." The use of this common 

 name for Gmelina Leichhardtii is an unfortunate one, as 

 it really belongs to the genus Fagus of the Cupuliferse. 

 The tree is a native of New South Wales and Queens- 

 land, and grows to a considerable size, reaching to a 

 height of 100 to 150 feet, with a diameter of over three 

 feet. It is a useful commercial timber, light in colour, but 

 with little or no figure, and thus cannot be classed as 

 ornamental, although it is useful for carving and similar 

 art purposes. 



The seasoned timber often has white particles filling the 

 cells of the wood, and these are sometimes so plentifully 

 distributed that the planed surface has the appearance of 

 having been filled, to a certain extent, with a substance 

 like plaster of Paris. When the timber is not sound this 

 substance often accumulates in "shakes " and cracks of the 

 wood as small opaque deposits and in crystalline masses. 

 The general appearance of the material when thus deposited 

 may be seen from the accompanying photograph, (Plate 

 VIII), which is of natural size. Under the microscope 

 these masses were seen to consist of needle crystals. 



The presence of some substance in "beech," different 

 from that of other native timbers, has previously been 

 observed by saw-millers, and in a letter from Mr. W. Smith 



