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84

Specimen Page of Computiko-book. Bection 9.— No. 3 Measurement. -I in. Invar Tape No. 02: .1 end, .1 edge. BETWEEN THE Bth AND 9th Tests. —DIFFEHF.NCKS FROM STANDARD. DIFFERENCES FROM STANDARD, (ll)ll DISTANI Ks. A end, A edge. IS end, A edge. A end, A edge. I! end, A edge. 1 = + -0028 1 = + -0037 TempJCoeff. = -OOOOOOie o=4- -(mil's 0 = + -00375 2 = — -0013 2 = — -0013 Hal. = 14-0404 lb. I = — (Mill 1 = — -00505 3 = — -0059 3= --0059 Sag. on 50 = — -00092 2 = — 00865 2 = —-00960 4 = — -0109 4 = — -010(1 U .61568 Ih. peroh. . 3 = — -01370 3 = — -01370 5 = — -0072 5 = — -(M 172 4 = — -00995 4 = — -01090

Notes. 1. In the heading, name of tape, end ami edge, (In- end stated as " A " means that this end is always leading in the direction of the measurement (or the section. 2. The letters " A " anil " H " in column 11 indicate the end of tape in use lor the particular measurement. 3. All "differences from standard" arc computed to a temperature of 02°. 4. Ti-niperatiiiv-eorrcetions are taken out of a table by inspection. 5. " Differences from Standard *' : When the measurements arc nominally full chains, the differences from standard arc taken out of the proper oolumn in the tables given in the heading to the left. When the measurements an- odd. as 372-1349. the difference lot the 3 chains lirst taken out of the table and proper column in the heading to the right, as '0137, and the difference for the odd links from a specially prepared link-value tabic as 4- 0039. li. Alignment : This correction also from a table is made to correct the small error introduced by the line measured being at one end out of the base alignment. (Sec Fig. No. 13.1 7. Sag : As the tape is supported on knife-edges every 50 links, the corrections lor sag are made on the basis of the number of 50-link lengths in the measurement. When there are shorter lengths requiring corrections, and a large number of them as in section 9. then these corrections arc most rapidly taken out by the formula, log. of sat; = ° 2 ' " afX '" ° '" s t- lon of distance ■'•. the lirst term log. 60". being a constant for the measurement. S. Mean tension : This correction is due lo the position of the constant tension of 15 lb., whether at the upper or lower end of the particular measure, it is rapidly taken out by inspection from graphic scales, one giving the correction find to the tension for degree ..I slope, and the other for the elastic extension of the tape equivalent lo the lirst -obtained correction. The final correction is 4 when the tension is at the lower end. and - when at the upper.

Fieldbnnk' to fieldbook. A -at I ill .2 t 9 (Torre Corrections. •ectiona. Seduced To ,.,„ Distances. lotals - UOOK. « s = I a / No. Patfc. 1 2 :l i Ei 3 s I empera- £ ture Correct inn*. 4 l I Miter. from Stand. a | Alignment. 7 Sag. 8 Mean Tension. tt ... .„, Measured Corrected , , .... , '"';' Distances Distances and &g„ a ? d ' r B ' corrected, inclinations. ' f,s """- in 11 12 18 14 if, JJ1Q»ill 2 26 0 Bidwill 2 26 0 57 _ OOOI 57 — •0001 f -0028 f -0028 •0007 - •0007 ■IMIlS ■(MIlS 4 + -(MMI2 99-8873 99-8871 L-9996090 + 0002 Kl. 0 15' 30" 9-9999956 1-9995050 99-8861 A 1 : 58 - -0002 -•(MI98 - -0IMI2 -0(164 I 22 -0001 — -0001 —-0176 3721349 - -0176 372-1173 1). 7° 24' 12" 85 2-5706713 9-9963644 2-5670442 - -0065 — -0137 X -98 + -0039 — -0064 369-0152 B 57 _ .(KNI4 —-(MI72 -(Midi -0092 x -99 = -IMIOI + -0013 — -0)55 409-9728 ■0 155 199-9573 Kl. 5 (Ml' 09" 64 2-6989266 9-9983426 2-6972766 498-0531 A 56 -•0004 •0100 -OOOL' -0071 -IMMII •0184 100-1378 — 0184 400-1194 D. 2° 31' 12" 102 2-11021794 9-9995798 2-11017694 B 399-7325 27 51 --0009 — -(H)72 ■IMIOI ■0092 1 -0007 •0167 499-9272 499-9105 — •01(17 El. 2 55' 15" 4 2-6988918 9-9994354 2-R983276 499-2609 !_ A I . : 2S 61 - 0048 - -0041 - -0007 (MK)li - (MM S 1/40 = — 0005 — -002:1 — •0077 140-3201 I 10-3124 — •0077 Kl. 0° 14' 20" A i 74 2-1470886 9-9999962 2-1470922 140-3112