The American watchmaker and jeweler; an encyclopedia for the horologist, jeweler, gold and silversmith .. . losed, measure two hundred and fiftythousandths of an inch in diameter. 10 11 12 ;lO O O O OO o o o o o o E^ 13 O ul 14 15 16 17 18 19 20 21 22 23 24 25 r- olO OOOOOOOOOOOOii \-^2& 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 :> I^O O Q O O O O^O O O o o o o o Op ^|;;42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60?i0 0000000oooooo<»999 0 ^ I J Fig. 149. These instruments can be furnished with millimeters (in the place ofsixty-fourths of an inch), and provided with a Vernie
The American watchmaker and jeweler; an encyclopedia for the horologist, jeweler, gold and silversmith .. . losed, measure two hundred and fiftythousandths of an inch in diameter. 10 11 12 ;lO O O O OO o o o o o o E^ 13 O ul 14 15 16 17 18 19 20 21 22 23 24 25 r- olO OOOOOOOOOOOOii \-^2& 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 :> I^O O Q O O O O^O O O o o o o o Op ^|;;42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60?i0 0000000oooooo<»999 0 ^ I J Fig. 149. These instruments can be furnished with millimeters (in the place ofsixty-fourths of an inch), and provided with a Vernier to read to one-fiftieth of a millimeter. On the bar of the instrument is a line of inches numbered i, 2, 3, eachinch being divided into tenths, and each tenth into five parts, makingfifty divisions to one inch. Upon the sliding jaw is a line of divisions,(called a Vernier, from the inventors name), of twenty parts, figured o,5, 10, 15, 20. These twenty divisions on the Vernier correspond in iiihiiihiiiliiiiliiiiliiiihiiiliiiiliiiiliiiiliiiiliiiiliii DarUng, Brown & Fig. 150. extreme length with nineteen parts, or nineteen-fiftieths on the bar, con-sequently each division on the Vernier is smaller than each division onthe bar, bv one-thousandth of an inch. If the sliding jaw of the caliperis pushed up to the other, so that the line o on the Vernier correspondswith o on the bar, then the next two lines to the left will differ from eachother one-thousandth of an inch, and so the difference will continue toincrease one-thousandth of an incli for each division till they again cor-respond on the twentieth line on the Vernier. To read the distance the 177 Gerbert. caliper may be open, commence by noticing how many inches, tenthsand parts of tenths the zero point on the Vernier has been moved fromthe zero point on the bar. Then count upon the Vernier the number ofdivisions until one is found which coincides with one on the bar, whichwill be the number of th
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Keywords: ., bookcentury1800, bookdecade1890, bookidamericanwatc, bookyear1892
