188 



SILK MANUAL, AND 



and value to many of our readers. — J^ew Bedford 

 Mercury. 



Mr LI^'DSEY : — If you tliink the following de- 

 scription of tlie method of preserving timber from 

 rot, insects and worms, now universally adopted 

 iu England, is of importance to the public, you 

 will confer a fivor by giving it an insertion. 



The writer of this is personally acquainted with 

 the ingenious inventor — has attended tlie lectures 

 in London on the subject, and is satisfied of the 

 efficacy of his plan. 



The mtUerial employed by the inventor is Cor- 

 rosive Sublimate, long known as a great preserva- 

 tive of animal substances from decay. The timber 

 to be ])repared must be placed in a tank or vessel, 

 from 40 to 80 feet long, 4 or 5 feet deep, and about 

 the same width. A solution of the corrosive 

 sublimate is then thrown upon it until covered ; 

 the proportion, according to the inventor, is 1 lb, 

 of corrosive sublimate to 5 gallons of water — 

 but individuals who have tried it, say 1 lb. to 10 

 gallons of water. Pine plank arre saturated in 48 

 hours. An oak stick, 40 feet long and one foot 

 square, requires three weeks — during which 

 time it becomes effectually seasoned, and will not 

 contract or shrink even on exposure to the highest 

 temperature of a tropical climate. The corrosive 

 sublimate has a strong affinity for the albumen or 

 vegetable juices generally called sap, combines 

 instantaneously with it, and-forms anew chemical 

 com[)ound which is solid, insoluble, and will not 

 attract moisture. The efficacy of this invention 

 has been tested in the most extraordinary manner. 

 Pieces of the timber prepared witb a solution of 

 the sublimate, and unprepared pieces, the latter 

 well seasoned, were placed in the " Rotten Pit" 

 at the King's Dock Yard, Woolwich, in 1828. In 

 1831, the writer of this was present when they 

 were withdrawn. The prepared timber was per- 

 fectly sound — the unprepared, although of the 

 best English oak, was a mass of rot and decayed 

 vegetable matter. 



The prepared sticks were left on the ground in 

 the open air six months, and then again |)laced in 

 the Rotten Pit with other pieces of weli'Seasoned 

 timber. At the en<l of two years, the prejiared 

 timber was found quite somid — the seasoned very 

 rotten. 



The Rotten Pit at Woolwich Yard is a cave 

 under ground, 80 feet long by 20 feet, and built 

 by order of government, for the purpose of testing 

 the efficacy of the various proposed nostrums for 

 •preserving timbei*. The pit is lined, top, bottom 

 and sides, with vegetable matter in the worst pos- 

 sible stage of corruption — very damp and full of 

 carbonic acid gas — it is a perfect hot-bed — a 

 candle will not burn in it a minute, so foul is the 

 air of this subterranean chamber. In fact, no 

 timber, although thoroughly salted, docked, or 

 seasoned, will resist three months the powerful 



decomposing qualities of the Rotten Pit. The 

 specimens were placed on the bottom of the pit, 

 and half buried in the putrid vegetable matter 

 with which the cave is kept supplied. This 

 experiment seemed so conclusive, that Covern- 

 ment immediately ]:aid the inventor £10,000, and 

 advised him to take out a patent. He was orilered 

 to construct tanks at all the Dock Yards, and the 

 government timber was immediately prepared in 

 the above manner. Previous to this, individuals 

 had fitted tanks, and two whalemen were built 

 entirely of timber and plank prepared with the 

 solution. House builders are also using it very 

 generally in London. The slee|)ers, or founda- 

 tions for railways — staves for oil casks, canvass, 

 rope, and all vegetable matter may be preserved 

 by its use. It is found that a cubic foot of oak, 

 will absorb three pints of the liquid, which will 

 cost at the present price of quicksilver, 7 1-2 cents 

 per cubic foot. A mere trifle compared with the 

 immense advantage of having a material not liable 

 to be destroyed l)y rot, worms, or insects of any 

 kind. The objection urged against this material 

 is, its poisonous nature. But it has been proved 

 by careful experiment, that corrosive sublimate, 

 when it combines with the sap of wood, forms a 

 compound perfectly insoluble, and quite innocent 

 — in fact a complete chetnical change takes place 

 in the poisonous nature of the mixture by this 

 combination. 



The writer has seen experiments tried upon 

 canvass and rope, which was immersed in the 

 solution, and placed four months in a dunghill — 

 the unprepared pieces were destroyed — while 

 the texture of the [u-epared specimens was not 

 weakened in the slightest degree — any one can 

 try this by using the above proportions. 



Satisfactory accounts have been received by 

 Messrs B. Rotch and M. Enderby, of London, 

 from the captains of the whale shijs constructed 

 at their instance, of timber prepared as above — 

 testifying that the crew were remarkably healthy, 

 although they slept actually in contact with the 

 ceiling plank thus prepared, through all climates 

 and changes of teuipcrature. 



it is well known to practical men that salt is not 

 an effectual preservative — as many ships salted 

 on the stocks have been found rotten the first 

 voyage — one instance, the Enterprise of Nan- 

 tucket. The Golconda, of New Bedford, has had 

 a new windlass three voyages in succession, and 

 the lower masts of ships very quickly decay. 

 These parts of a ship it is imposoible to salt. In 

 the British navy the use of salt has been discon- 

 tinued, as it is found to corrode the iron rapidly, 

 and it also keeps a ship in a very damp state. 



Remedy for the Croup. — The Medical and 

 Surgical Journal of March last, contains a com- 

 munication from Dr J. D. Fisher, of this city, 



