228 THE POPULAR SCIENCE MONTHLY, 



ble substances, and disperse themselves through the air, and fall to the 

 soil for its enrichment. 



The pith of the whole matter is this : Cannot the dead body be, by 

 some chemical process, metamorphosed into stone, and then reduced 

 to powder, for preservation, like ashes, in the funeral-urn, or scattered 

 to the winds of heaven, to seek its normal starting-point for future 

 transitions ? 



A jS^EW PROCESS FOE THE PEESEEyATIO:^r OF 



WOOD. 



By M. a. HATZFELD. 



THE question of the preservation of wood, applied to the sleepers 

 of railroads, telegraph-poles, and wood for mechanical purposes, 

 etc., becomes from day to day more urgent, in presence of the increase 

 of railways. Of all the materials employed until now, there remain 

 hardly two in use — sulphate of copper and creosote. 



The sulphate of copper gives only imperfect and very variable re- 

 sults. This we can easily understand : this very soluble salt must be in 

 part diluted by rain-water and the humidity of the soil, so that, at the 

 end of a certain time, the preservative effect has disappeared. Be- 

 sides, this process very often causes alteration in the wood from the 

 impurity of the salt employed, or from its acid reaction — circum- 

 stances which it is very difficult to avoid, when we operate on a large 

 scale with materials containing, in a state of combination, an energetic 

 acid, having for its base a metalloid, such as chlorine, sulphur, nitro- 

 gen, etc. 



As to creosote, it is a substance comparatively rare, of a high price, 

 of an inflammable nature, and, in consequence, difficult to transport and 

 handle. Besides, and this perhaps is the most important considera- 

 tion, it is a product which, like those we extract from fossil-coal, may, 

 some day or other, in consequence of a discovery analogous to that of 

 aniline, acquire a high industrial value. Its employment would then 

 become impossible for the preservation of wood. 



Hence we may say that these two substances do but imperfectly 

 comply with the necessary conditions, and the question arises, whether 

 there is no other material that might be used in all our present yards, 

 i. e., that might be injected equally well by Boucherie's process (gravi- 

 tative force of a heavy column of liquid), and by the modified process 

 of Breant (successive action, in a close tank, of a vacuum and of a 

 pressure of several atmospheres). I propose the acid tannate of protox- 

 ide of iron, and base my views on the following considerations: 



Wood, as we know, consists of cellulose, or cells in which there is 



