ENGINEERING AND ARCHITECTURE. 561 



sufficient number of caps, the fixing of which would not occupy more than the 

 attention of one man. The pumps at a cost ft' |30 or $40, would be worked by the 



motive power of the mill. The utility of this simple invention cannot be over- 

 rated, when we consider that Canada produced in 1853 the enormous quantity of 

 218,480,000 feet of lumber, and 38,140,000 cubic feet of squared timber, which 

 would be worth, as declared by the Government accounts, £2,855,255. This is 

 entir sport, and we may safely estimate that the quantity required 



for home consumption, for railroads, bridges, shipping, houses, &C, must con- 

 siderably exceed double this qu otity, Any method which can be adopted to 

 prevent the ravages of dry rot and decomposition, must prove an absolute saving 

 to the country to a very considerable amount. These processes which we have 

 briefly attempted to describe, seem to embody the requirements of simplicity and 

 easiness of application ; and, if they are proved by practical experience to accom- 

 plish all that their patentee promises, could be introduced, at a very slight 

 expense, in the largest as well as the smallest lumber mills. With such a simple 

 method, our houses and bridges might be made capable o'l lasting au indefinite 

 period. 



It is worthy of notice, in reference to these processes, that they serve in some 

 degree to illustrate the small amount of pressure which nature seems to employ 

 in the growth of trees. We here find, that with ahead of twenty-rive feet, water is 

 driven, in about thirty seconds through a tree 16 feet long ; so that in the natural 

 process of the sap rising, the pressure must be scarcely perceptible, and probably, 

 is nothing mote thu capillary attraction. When looking at the end of a beach or 

 oak log, with its extremely minute pores, it would scarcely be believed that so 

 slight a pressue could force the water through its minute channels, yet such ap- 

 pears to ho the case, and it is owing to this wonderful provision of nature, that 

 by the processes detailed above, these same pores may be employed as means of 

 drying and seasoning the wood ; or conveying through tbem, to the innermost 

 heart of the tree, chemical substances, to render it incombustible, or completely 

 to impregnate it with any coloring matter we may d i . 



Scarcely anything strikes the observant traveller fresh from Europe, on his 



first arrival in Canada, more than the extent to which wood is used; especially 



cat public works, such as Railway viaducts, and bridges of all kinds, in piers 



and esplanades, and in many parts of the mo4 substantial buildings, for which 



stone or iron would alone be considered suitable in Europe. The cause of this 



i the great abundance, slight cost, and facility in working, of the 



it qualities we can only add of the 



'one mi i iron, by such economical processes as those referred to 



above; aHd further render it incombustible, as has been effectually, though not 



yet economically done, by Kyan's methods, the value of the results to Canada 



would bi almost incalculable. One, if not both of these most desirable objects 



Mr. Tomkins, of Hamilton, believes he has attained; and we can only hope his 



processes will be fairly and fully tested : and that if they prove successful he 



el with the reward he v. id be so fully entitled to. 



F. W. C. 



