642 General Notices. 



cattle, &c. Provide stakes of larch, willow, or other round wood, rather 

 straight, 6 ft. long, and about 3 in. in diameter, making use of the waste ends 

 by cutting them into 3-inch pieces; then take rod iron in 6-feet lengths, turned 

 up I in. at one end and pointed at the other. Thus prepared, burn holes with 

 a piece of the iron rod through the stakes, 12 in. from top and bottom, in the 

 same direction ; and through the centre of the small 3-inch pieces from end to 

 end, having ten of each. Run the iron through them alternately, commencing 

 with a stake, ending with a 3-inch piece; then bend the whole circularly round 

 the tree, tying it to the other side by twisting the spare iron rod (about 10 in.) 

 round the next stake. Thus any handy labourer may fence in trees in a simple 

 and durable manner. But experience has taught me to drive three larch 

 stakes, 3 ft. long, half-way into the ground, at equal distances, within the circle 

 of the guard, to keep it in an upright position, or else cattle will force it 

 against the trees, and the bark often gets injured by the upper part of the 

 guard. Bamboo cane makes a very ornamental fence as above, and in some 

 situations would be desirable. Trees should be strong, 8 or 10 feet high, and 

 well rooted, before they are planted out singly, and ought not to be cooped up 

 in large cumbrous cratUes, as we often see, excluding rain and air. (H. Bowers, 

 Laleham, Gardener and Forester to the Earl of Liican ; in Gard. Chron. for 

 1841, p. 365.) 



Dr. Boiiclierie's Mode of preserving Timber. — The substance employed is im- 

 pure pyrolignite of iron ; and the method of saturating timber with it is to take 

 advantage of the vital forces of a tree while in full vegetation, and to present 

 the pyrolignite to the lower extremity of the trunk, as if it were food to be 

 taken up into the circulation. Upon trial, this mode of impregnating the 

 trunk was found perfect, the pyrolignite rising rapidly through all the per- 

 meable parts of the timber up to the extremities. The method employed is 

 simple immersion of the lower end cut off, when small arms of trees are to be 

 operated upon; but when the weight of large timber trees prevents their 

 being so treated, without expensive tackle, the following contrivance has been 

 adopted : — At the ground hne a hole is bored horizontally through the trunk, 

 so as to open a passage from side to side ; a coarse-toothed saw is then 

 introduced into the hole, and worked right and left horizontally, till about 

 1 in. in thickness remains undivided on either side ; by which means nearly all 

 the sap-vessels are cut through, and the trunk remains supported by two 

 opposite points. The wound is then carefully closed externally with pitched 

 cloth, except at one point, through which a pipe passes from a reservoir con- 

 taining the pyrolignite. A few days in the summer or autumn are sufficient to 

 saturate a large tree ; for which purpose, pyrolignite to the amount of about 

 •^ of the weight of the green wood is required. In France, the hoops of 

 wine casks are made from branches of sweet chestnut. Some casks hooped 

 with wood thus prepared, and others in the usual state, were placed side by 

 side in a damp cellar ; at the end of two years the natural hoops were rotten, 

 while those prepared were unchanged. Timber thus impregnated becomes so 

 hard and tough as to be very difficult to work. (^Gard. Chron., vol. i. p. 147.) 

 Subsequently, Dr. Boucherie succeeded in charging timber with his prepa- 

 rations during winter as well as summer. For this purpose, the timber is 

 cut into any lengths that may be convenient ; to the upper end of each log a 

 water-proof funnel or bag is secured, into which the preserving fluid is poured. 

 The fluid forces before it all the sap and air that the wood contains, and with 

 considerable rapidity ; and when the preserving fluid makes its appearance at 

 the lower end, the operation is complete. {Ibid., p. 231.) 



M. Biot, one of the most eminent of French men of science, thus expresses 

 himself on Dr. Boucherie's experiments. After observing that they are 

 founded on the discoveries of Hales, of the ascent of liquids in vegetables by 

 the double power of suction belonging to their roots and the exhalation be- 

 longing to their foliage, he says, — " In considering the woody tissue as a 

 natural mould, capable of being transformed by injection into a new body, 

 endowed with special qualities for practical uses, M. Boucherie has conceived 



