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On the mischiefs arising from the employment of fir, pine, and cedar, in packing astronomical and surveying instruments, time-pieces, &c
Precautions in Packing,--and i n Powder Mills.
SSI
On the mischiefs arising from the employment of ~ r , `,Pine, and Cedar, in packing dstronomieal and Surveying Instruraentsi 7;ime-pieces, ~'c. BY T~o)xas GILL, Esq. M ~ v years ago, the Editor was shown a sarveying instrument by its maker, Mr. E. Troughton, F~. R . S~. which " had been sent to a hot climate, and was returned to him that it might be put into order,, as it was covered all over with a viscid coat of varnish, which had entirely prevented the motion of the sliding parts of it; in fact, i.t required to be taken to pieces, to have its coat of securing varnish removed, and to be again ti-esh varnished, to fit it for use. These evils were occasioned by the employment of slips of cedar in the packing, as it is termed, of the instrument in its mahogany box; and wouht prove, as he said, a salutary lesson to him, against ever empt oyin~ so nfischievous an article in future. [t is fact has been lately recalled to the Ed[tot"s notice,by another~ and a sotaewhat similar circumstance. Mr. I. Lukens being about to return to the United States, and having had a marine chronometer made, required a packi~.g case to enclose tl~e mahogany box, containing it; he~ however, stated that he shouhl carefully avoid the use of one made of pine, as a volatile varnish was disengaged fi'om it, which would thicken the oil applied to the movements of the chronometer ! Of course, equal care should also be taken to reject the shavings of fir, pine, cedar, and other similar woods, which are ordirlarily empl~ved in filling up vacancies within and around packages, m" the sa~ne evil resutts will certainly be experienced; and it shows from what seemingly trifling causes, the very worst effects, in respect to the performance of these and other delicate instruments~ may be ,6ffen produced. ~Ib.
.Fire produced by the collision of copper, ,ge. AL'rr~OUGHgreat care is taken to exclude fi'om gunpowder manufitctortes all articles of iron, and to substitute copper and other metals which wilt not strike fire, in the metallic parts of the machinery, vet: it is well known that explosions, attended with disastrous consequences, are very frequent. Excited by an occurrence of this nature,.4L dubert, Col. of artillery, was induced, in conjunction with Capt. Tardy, to resume some experiments which he had unsuccessfully tried, to ascertain, whether gunpowder would not explode by the shock of copper. The result of these renewals was, "that powder wouhl inflame by the stroke of copper upon copper~ or upon the alloys of Copper. This gave rise to further investigations, in presence of the committee of sa{'ety, and it was ascertail~ed that gunpowdel could be exploded b,/the strok~ of iron upon iro~ ; troll upon cop))er eolq~er upon copper:, iron up,m ~arh/e ; ;rod by using the b,n.listii:
SSI
On the mischiefs arising from the employment of ~ r , `,Pine, and Cedar, in packing dstronomieal and Surveying Instruraentsi 7;ime-pieces, ~'c. BY T~o)xas GILL, Esq. M ~ v years ago, the Editor was shown a sarveying instrument by its maker, Mr. E. Troughton, F~. R . S~. which " had been sent to a hot climate, and was returned to him that it might be put into order,, as it was covered all over with a viscid coat of varnish, which had entirely prevented the motion of the sliding parts of it; in fact, i.t required to be taken to pieces, to have its coat of securing varnish removed, and to be again ti-esh varnished, to fit it for use. These evils were occasioned by the employment of slips of cedar in the packing, as it is termed, of the instrument in its mahogany box; and wouht prove, as he said, a salutary lesson to him, against ever empt oyin~ so nfischievous an article in future. [t is fact has been lately recalled to the Ed[tot"s notice,by another~ and a sotaewhat similar circumstance. Mr. I. Lukens being about to return to the United States, and having had a marine chronometer made, required a packi~.g case to enclose tl~e mahogany box, containing it; he~ however, stated that he shouhl carefully avoid the use of one made of pine, as a volatile varnish was disengaged fi'om it, which would thicken the oil applied to the movements of the chronometer ! Of course, equal care should also be taken to reject the shavings of fir, pine, cedar, and other similar woods, which are ordirlarily empl~ved in filling up vacancies within and around packages, m" the sa~ne evil resutts will certainly be experienced; and it shows from what seemingly trifling causes, the very worst effects, in respect to the performance of these and other delicate instruments~ may be ,6ffen produced. ~Ib.
.Fire produced by the collision of copper, ,ge. AL'rr~OUGHgreat care is taken to exclude fi'om gunpowder manufitctortes all articles of iron, and to substitute copper and other metals which wilt not strike fire, in the metallic parts of the machinery, vet: it is well known that explosions, attended with disastrous consequences, are very frequent. Excited by an occurrence of this nature,.4L dubert, Col. of artillery, was induced, in conjunction with Capt. Tardy, to resume some experiments which he had unsuccessfully tried, to ascertain, whether gunpowder would not explode by the shock of copper. The result of these renewals was, "that powder wouhl inflame by the stroke of copper upon copper~ or upon the alloys of Copper. This gave rise to further investigations, in presence of the committee of sa{'ety, and it was ascertail~ed that gunpowdel could be exploded b,/the strok~ of iron upon iro~ ; troll upon cop))er eolq~er upon copper:, iron up,m ~arh/e ; ;rod by using the b,n.listii: