528 The yotirnal 0/ Forestry. 



been clearly proved by various severe tests. Two pieces of Scotch fir, 

 cut from the top of the same tree and from each other, one prepared 

 and the other unprepared, were crushed to destruction, the former by 

 a load of 27 tons 10 cwt., while the latter succumbed to a load of 17 

 tons 10 cwt. In the same way, in the case of two pieces of pitch pine, 

 the prepared stood 37 tons 10 cwt., the unprepared 22 tons 10 cwt. 



With a view to substituting pitch pine for American white oak for 

 carriage and waggon building, the North British Eailway Company cut 

 a piece of oak and a piece of pitch pine exactly the same size, viz.. Sc- 

 inches long by 3| inches by 2| inches ; the pitch pine was prepared, 

 and both tested by being crushed to destruction at the company's 

 works at Cowlairs. ^The prepared pitch pine gave way with a load of 

 90 tons, while the oak, in its natural state, gave w^ay at 47 tons 10 cwt. 

 White pine (spruce) was also tested by them : two pieces were cut from 

 each other, and exactly the same size, viz., 3^ inches long by 2f inches 

 by 2^ inches ; the prepared one gave way at 35 ton3 load, the unpre- 

 pared one at 25 tons. 



The increased density of the prepared timber over the unprepared 

 gives the former this valuable quality, that it expands and contracts 

 much less under changes of temperature and of moisture than the latter. 



The process furtlier affords a ready means of impregnating timber 

 with liquid cheu deals, which, while preserving the wood from decay, 

 will render it invulnerable to the destructive ravages of the Teredos 

 navalis, Limnoria, the white ant of India, and all other worms and 

 insects which prey upon timber ; and by the kindness of Sir John 

 Coode, C.E., an opportunity has been offered Mr. Gardner of putting 

 this to practical tests, by exposing timber so preserved to the free 

 attacks of the Limnorna at the Douglas Harbour Works, Isle of Man, 

 and to the Teredos at the Pier Works, Gorlestone, near Yarmouth, and 

 at Colombo, Ceylon, 



The process is also of special advantage to the builders and owners 

 of hothouses, as hitherto the only serious objection to the use of 

 wood for hothouses has been its liability to rot and decay when 

 exposed to the action of a hot, moist atmosphere, as in the case 

 of stoves, pine-pits, forcing-houses, vineries, and, indeed, in all horti- 

 cultural erections where a warm, moist temperature is requisite. It 

 is quite impossible to get any timber, in its natural state, thoroughly 

 j)roof against this tendency to rot and quick decay ; hence the import- 

 ance of the discovery of the Gardner Preserving Process as applied to 

 hothouse building. It not only extracts the sap or decayable matter 

 from the wood, and so seasons it thoroughly, but at the same time 

 renders it proof against either damp or dry-rot. The expense of 

 applying this valuable process does not amount to more than three per 

 cent, on the entire cost of the buildiiiu'. 



