New hwented C~'ane.
413
¢wry description, such as dripping, pot Mdmmings, ,~'e. a pound of which, value about 5d. will continue, fi~r ful| twelve hou~s¢in a common-sized dissolvent argand burner, to yield light equal to eight candles~ being no more than a farthing an h o u r ! ' . " ~ ...... ~ " [Registd~ o f the Jlrts,. • New Invented Crane. IN the October number of Newton's Journal, he has given the sub. ~ joined account of a new invented crane. We shall,hereafter, ob: htin further particulars of its construction, and wegreatly err-iri Oia, ,jud"ment,.~ if its operation. .will. be found to justify the ekpei~tafiolaS wlHcb the present pubhcatlon is calculated to excite. W e may find an improved instrument, in wbich the power is moire conveniently applied, than in those heretofore made, the friction m/ty be lessened, and the obstruction from the rigidity of cords~ or othi~'r causes~'~may be, in some measure, obviated; but should the effective power of men be increased, in the ratio represented, we must obtain some flew mechanical. . power, acting upon. new. ' laws of nature;' perpetual toO, Oon will no longer be an impossible problem, and we shall ' be condemned to study, again our experimental philusoly)h ,' and, rearran,~e, s' all the machinery operated upon by the power of men. J'he tolloWing is Mr. Newton's account. [Editor. "Mr. L. W . Wright, has ju.~t completed a crane for raJ%ing heavy bodies, which is constructed upon very different principles to any crane that we have before heard eL It is without either wheel or finion, and acts by an extremely simple adaptation of wedges and evers. There is one extraordinary property, in this peculiar combination of mechanical powers, which appears to shake the validity of an old established axiom, that " power can only be increased at the expense of velocity," for this crane does actually raise heavy weights with less than half the power of the best constructed cranes heretofore used, and with the same, or even greater velocity. "Mechanics have considered a curtain general rule of power compared to velocity, to be established, which, if we are not mistaken, is, that two men will raise 600 ewt. at the rate of tenfeet Ter ntinute, by any of the known simple combinations of tbe wheel and pinion, or other mechanical powers; or, in other words, that oneman Will constantly exert a power equal to SSlb. during the hours of daily labour, which, beinz multiplied by ten, the assumed power ~ained by the machinery, and allo'wing 1-7th for the friction, leaves a~bout 500 cwt. per man; and in all cases where the machinery is so constructed a s to increase the effect of the power exerted to raise the heavy body, the velocity, or space through which the heavy body move~, must¢ accordingly, diminish. : ~' Several of these cranes have been lately erected at tim West i India Docks, anti it has been proved, that, while two men raise, (as above said,) 600 cwt. at thd rate of ten feet per n finute, by the o f dinary cranes, two men, with the improved crane, will raise more than 1500 cwt. through the same distance, in a similar space offime.
t
414 Iq:ltJ~ixs's Nteam Ea~qne--Cheay a'ml Dur~tble Cemclzt. " T i m al)lJllcation of (lie mecilanieal i)rhteil)les, i)li x~tllcll this cralle is construeted~ is adinitte(l~ by all ~(ho trove seen it~ to be ])erfectly lleW, and its perfol'nlance, ill every respect, satisfactory. ~IVe are not at liberty to dese,'ibe its construction, at present, as'the patents tim Scotland~ Ireland, and other ooutltries, are tier yet complete, lie,' is the specification of the English patent~ yet iiu:olled; but> its soon as lhe invention can safely be made public, we shall la$' it before out" readm's."
PEal¢l~S'S
Steara Engine.
M~t. ['vau~lys~s engine, erected at St. Catheriue~s l)ock, ha~ i)~:eu, occasionally, at wo,'k, raisiug water, since out" last notice, art(l, ;ts we are inlbvme(l~ with all the ett'ect desired. Mr. 1'. J~as m)w erected at his new factor~', near Regent Square, Gray's hm Road~ a very complete engin% havin~ two slnzle stroke evlinders~ connected illgerber, both. worked with high pressure steam~, The steam is admitted from the generator, through a very small induction apevtu "e, at the h)wer part of t}le first c.ylhMer, (whic x is a small one,) at a t)resstu'e~ it is stated~ of about ()lie ]lun(hcd atiniispheres, ;uid, wh(jn the [)iS{Oli has been forced up olle eighth of its stroke, ttw induction al;ertureis closed. This vo!ulllQ,of stealll ll()W eXlml(l]iig ;, drives tile liist(m to the top of the cylinder, where all eltial'~elilelil; of the cylinder allows the slealu [o escape ;list the piston, alid thl'otl~h it iJa~<~a~c (0 tt~,e upper p;crt of tile [algel- cyliuder, co mected It) it, wiml'%.. .',cti,l(,'~ ... with it .di iiillished, force, (.).s~l'aDo,it, tell atlnosl)heres, ) it drives ti~e larger piston, to tile bottom of its cytinde)-, and (he;~ bc,ili'.t," colmecte(] toocetl!(2r~ and lhe steam e n tering-, t ( we c~.. hiders., at (<~.~posite ends, to [a)" the }_~lilJ joel fully belbre out" readers.
E"~'to~z'a aouma:Jh~, o,t.
Oa the Prel)C(ratio~of a Cheap and Durable Cement, or &'veto.
l;y
5!. I~,ss,uc;.xE. Tuv. ~ritm- observes, flint the cement or plas~cr, couunolily used in I('railc('~ (~hh:h ~onsists of a mixture of cMlk: aiM stroug size)