178 



THE GARDENER'S MONTHLY 



[f/un«, 



We know of (ino |)lace wlicre n mill r<nil(l l)C lo- 

 cated within oifiht miles of the valley, and be in 

 the heart of a forest of a hundred square miles. 

 A road on a prade of one foot to the rod would 

 reach it within the distance named. Another 

 large f<irost stand.s within five miles of a traveled 

 road. At Dillon's mill, lumber has been delivered, 

 during the hu^t year, over a wooden railroad which 

 has a grade of 1000 feet to the mile. The cars 

 run down loaded, by their own weight, and are 

 drawn hafk by a mule. Mr. Dillon has found 

 that his system of brake will stop a car on a 

 grade of live feet to the rod. A singular fact in 

 his experience is, that a loaded car will mind the 

 brakes when an einpty one will slide with all 

 wheels locked. This seems owing to. the fact 

 that the face of the wooden rail gives under a 

 load. As to whether this plan of delivering lum- 

 ber will prove as satisfactory as the V flume, 

 time will determine; but, doubtless, either will 

 prove greatly superior to the teaming S3'stem, 

 and probably would suflBce to stop the carriage 

 of lumber through our valley. — Vhalia Iron Age. 



The Preservation of Timber. — Buried in the 

 earth or exposed to the air, timber rapidly dete- 

 riorates, and undergoes the species of decompo- 

 sition known as dry rot. This decomposition 

 may be retarded by the application of a coat of 

 paint to the timber exposed to the air, or by car- 

 bonizing the surface of that which is intended to 

 be sunk in the ground. 



During the last twenty years, several methods 

 have been tried for making timber more durable, 

 the principle of which consists in expelling the 

 sap remaining in the ligneous fibres, in order to 

 replace it by chemical solutions, such as sulphate 

 of copper and creosote ; but these processes, 

 comparatively costly, and only partially success- 

 ful, do not entirely accomplish their object. 

 Starting from the fact that oak, chestnut, and 

 certain American trees resist the action of air 

 and damp, better than others, and that they owe 

 this property to the tannin which they contain, 

 a chemist proposes to tan the timber by substitu- 

 ting for the sulphate of copper and creosote a 

 compound of tannic acid and iron. The abject 

 of injecting various substances into wood is to 

 poison them, so that germs and microscopic 

 growths may no longer live and propagate either 

 on the surface or in the interior. Now tannin is 

 one of the most active and certain destroyers /of 

 germs both vegetable and animal, which fact ac- 

 counts for its preservative agency. Besides, it is 



to tannin that irt due the almost indefniite pres- 

 ervation of leather. One peculiarity to be noticed 

 in this process is, that timber treated with thia 

 compound of tannin and iron, that is to say a com- 

 jiosition similar to ordinary writing ink, is turned 

 black. 



The process of injecting timber with tannate 

 of protoxide of iron is due to M llatzfeld; the 

 Eastern Railway Company of France has ex- 

 perimented with it on some sleepers, and the 

 Telegraphic Department on some posts. 



M. Boucherie has denied in a note to the 

 "Academic," the efficacy of this process, con- 

 tending that the attempts already made to pre- 

 serve timber from dry-rot by injecting it with 

 iron salts have yielded only partially successful 

 results, while sleepers treated by sulphate of cop- 

 per have lasted twenty five years and more. 

 Reply is made to these objections by quoting — 

 not the experiments of the laboratory or the 

 workshop, but those made by time itself. It is 

 not a rare circumstance to encounter in earth of 

 a ferruginous nature the trunks of very old oaks, 

 blackened and very perfectly preserved ; at 

 Rouen, in 1^30, some old oak paling was discov- 

 ered as black as ebony, and dating back to the 

 Middle Age.s. Not very long ago, too, a Norman 

 vessel built of oak was discovered in an almost 

 perfect state of preservation in the neighborhood 

 of an iron mine in Norway. It is more than 

 probable that the preservation of the oak under 

 these circumstances is due to the tannin con- 

 tained in the wood ; it follows, therefore, that by 

 introducing a substance rich in tannin into tim- 

 ber that does not naturally possess it, its resist- 

 ance to decay is increased. — Journal of the Society 

 of Arts. 



Selecting Timber. — In selecting timber, the 

 surveyor's attention will naturally be given to an 

 examination of the butt or root end, which should 

 be close, solid, and sound ; and if satisfied in this 

 respect, the top should next be inspected, to see 

 that it corresponds with the butt-end. Afterwards 

 be will glance over the exposed sides in search of 

 defects, carefully examining the knots, if any, to 

 see that they are solid. He will, of course, avoid 

 any piece that has either heart, cup, or star-shake, 

 or sponginess near the pith at the butt, discolored 

 wood at the top, splits along the sides, rind-gall, 

 worm holes, or hollow or decayed knots. In 

 dealing with spar-timber, he will select the 

 straightest pieces ; they should be free from all 

 the defects before mentioned, upsets, i. e., fibres 



