Page:Willich, A. F. M. - The Domestic Encyclopædia (Vol. 3, 1802).djvu/384

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562] FED pl'^tes, representing the separate spokes, and each of hich iucludes two links of tiie chain above-men- tioned ; the twelfth spoke being divi'ed at its foot, for comprehend- ing the 25h Jink. E, An iron axis, being a screw ■with 320 circumvolutions, each of which is marked separately on an engraved index on one of its sides : and, in order to apply this part of i{*e njachine, it is screwed firmly inro the stock of the wheel, with ■which it revolves when in motion. F, A .<:t://i'-, or niul-ade, being an expanding screw-nut, thatcmbraces the axis, along which it screws, as the latter revolves with the wheel ; 2nd, as each revolntion describes an exaiSt longitudinal pole (four of which are computed to a chain), the style being pendent, and mov- ing towards its proper figure, de- nc'ies the length of ground passed ; as it is divided intv) chains and poles en the index of the axis £, and into linlis on the piriphery C. G, is a small adjusting screw ; •which being turned, the style may be removed to the beginning of the index, alter the given line, in sur- veying or measuring land, has been ascertained in chains, poles, &:c. H, represents a cross, or square, v:ix s.h-jh.is, for determining per- pendiculars in laiid-measuring. It is su.sj;ended at its ends on the axis, V. hence it may be occasionally de- ti»ehcd b)' a hiniple touch ot the finger and thumb, when in use. ■ Panher, ihis cross prevents the style from being revolved with the axis by any accident. As the 320 (livisiens marked on the index of the axis E, describe a mile, the Myle F, after having passed over f tm, will stop: and, as it will ii<;w move round with the axis, it v»ill carry with it the standard ; FED which win strike on the wrist of the operator, and thus prevent him from proceeding to any farther dis- tance, till he withdraws his hand from between ;5uch standard and the axis. Having receiv d this hint, he turns thj screw G) puts the style F back to the bottom of the index, and continues the revo- lution of the machine, till he has completed his course. Mr. Tugwell's contrivance is particularly calculated to prevent error in measuring land ; as one person n.y tims survey wiih greater accuracy and expediuon, tiiau by the use of the chain alone. Be- sides, no fraud can possibly be committed by labourers, in niea- suring task- work ; a circumstance of tiie utmost importance to agri- culturi-ts. The last contrivance, we have been requested to mention, is that of IVIr. Ralph Gout, of Bunhill- row, London ; whose ntn- pcdro- meticral paleiit-wafch ciifi^'ers from the instrument invented by Mr. Frasek, in this essential circum- stance, that the former is conneft- ed with a time-piece, while the latter is combined w.tli a compass. Those who live in the metropohs, or visit places, the situation of which is known to the traveller, v iil perhaps give the preference to Mr. Govt's capped metal watch with a pedometer, which he ma- niiia(3ures by subscription for 15l. Jjs. (or the pedometer alone, for Si. Ss.) : — on the other hand, wc cor.ceive, persons residing in the country, es|-tc:aliy sjjortsmen, who are generally provided w ith a watch, on their excursions, will probably fin.; Mr. Fkasek's pedon:cter, on account of its compass, the more useful instrument. I'LLLITOK Y - or - T H E - Wa l l, tiie