HORTICULTURAL JOURNAL. 333 



a space between it and the wood, sufficient for the preserving, to keep in 

 contact with the freshly cut surface of the tree. The liquid is brought 

 there from a tub or other reservoir, by the help of a slanting hole made on 

 the upper side of the tree and in which is put a tube adapted at its other 

 extremity, to a spigot in the upper reservoir which contains the solution. 

 A pressure of five metres suffices, so that the instant the sap of the 

 tree is driven away, it escapes and is replaced by the liquid saturated with 

 sulphate of copper. As soon as the operation terminates, and it lasts some 

 hours for the most difficult logs, the wood can be sold and put to any use. 



M. Decaisne enumerated the immense advantages which this process 

 would procure to horticulture. Boxes, frames, greenhouses, supports, 

 &c. &c, submitted to the so deleterious action of all the exterior agents, 

 which destroy them so rapidly, all can acquire, so to speak, an indefinite 

 duration, and thus furnish a very great economy of time and money. M. 

 Decaisne opposes the processes by simple immersion. He demonstrates 

 that in these processes, the impregnation is too imperfect ; he shows that 

 wood dried, and consequently filled with air, opposes an insurmount- 

 able force to the penetration of any liquid. According to M. Decaisne, 

 dried woods immersed in sulphate of copper, are no more safe at the heart 

 than wood on which have been applied a coat of color, varnish, pitch, &c. 



M. Andry asserts, that he has obtained excellent results by these last 

 processes applied to the wood of his greenhouse, to the supports which he 

 employs, and especially to the coverings and curtains, serving as shelter for 

 his greenhouse, these shutters and curtains, exposed to every cause of de- 

 struction, having lasted eight years after being immersed in a solution of 

 one kilogramme of the salt to eight litres of water. M. Decaisne showed 

 that this proportion is too weak for young pines which have little heart, and 

 in which resin itself forms a combination. He regards the quantity of two 

 kilogrammes of the sulphate, to a hectolitre as being more fit. He thinks 

 that M. Boucherie possesses in this subject, results of experiment which are 

 wanting to him. M. Decaisne also remarked to M. Andry, that his expe- 

 rience and observations were not comparative ; that in the case of cover- 

 ings, of cloth or of curtains, the liquid could wet completely, the fibres of 

 his cloth and cords, &c., but it is not the same for timber which we wish to 

 entirely moisten ; nothing is easier than to steep cloth into water and to 

 soak it ; nothing is more difficult than to deprive the dried trunk of a tree 

 of the salts which it contains. The wood destined for naval construction, 

 and which are left several years in the basins, are an example. M. De- 

 caisne asserts, that in plunging into the same liquid a cube of dry wood, 



