DESCRIPTION OF THE CHIEF FOREST TREES, ETC. 3] 



remained for some time in a state of rest. The most exceptional and 

 important property which, the Victorian oils exhibit in their relations 

 with resinous substances, is the power they possess of dissolving the 

 fossil Kauri Gum (Dammara Australis) of New Zealand. This 

 substance can be obtained at a very low price, from 10Z. to 121. per ton ; 

 but the difficulty of bringing it into perfect solution, has hitherto 

 retarded its exportation in large quantities. The solution of the above 

 named resin, bears dilution with very strong alcohol, ether, and chloro- 

 form to any extent, and about 30 per cent, of turpentine may be added 

 with safety ; but 50 per cent, of that solvent throws down the resin as 

 does spirits of wine, benzine, linseed oil, and coal oil (kerosene). The 

 solution of sandarac may be diluted with strong alcohol ; but turpentine 

 and linseed oil cause the deposition of the resin. Asphaltum is thrown 

 down by the absolute alcohol ; but turpentine may be added with im- 

 purity. Grass-tree resin on the contrary is held in solution by alcohol, 

 but will not bear dilution with turpentine or linseed oil. Mastic may 

 be diluted with all the ordinary solvents, but alcohol in quantity 

 appears to precipitate a portion giving rise to a milky ap23earance. 



With a view of testing the durability of varnishes prepared with 

 essentials oils of the genera Eucalyptus and Melaleuca, many experi- 

 ments have been undertaken ; numerous surfaces coated with them, 

 and with varnishes of established reputation, have been placed in 

 sheltered and exposed situations, and the effects of sun and moisture, 

 and of shade, compared and noted from time to time ; but the results 

 obtained are as yet too imperfect to admit of their embodiment in the 

 present report, investigations of this kind requiring much time for their 

 satisfactory completion. 



DESCRIPTION OF THE CHIEF FOREST TREES OF UPPER 

 CANADA. 



BY DR. HURLBERT. 



The samples of wood about to be described, sent to the International 

 Exhibition, have been collected from the extreme eastern and western, 

 and central parts of Upper Canada, for the purpose of showing the 

 extent of country over which the most valuable timbers grow. 



1. The most important collection is in the form of planks, twelve 

 feet long and four inches thick, with the bark on both edges. Of these 

 (sixty in numb er), there are superb samples of white oak, four feet 

 wide ; white wood, black cherry, black walnut, button- wood, white ash, 

 sugar maple and soft maple, from three to four feet wide ; one plank of 

 pine, from the township of Bayham, twelve feet long (and it could have 



