238 REPORT—1905. 
TasLe A.—Length of 480-foot Ground Base Determined by Measurement 
with the Steel Bars. 
Date Temp. (F.) Length of Base 
1904 n mm, 
May 25 . . G : «69 146308°75 
ee 2 . : Or “71 
June 2. . : . Pe (i “49 
” 7. . . . . 59 “58 
hele P P . at iO “43 
aoe LB ke . : ‘ - 59% 68 
re A) oe 5 - Oe “83 
» 25%. : : se *b9 
99 Gee 2 : : - 68 “77 
eth R : : =f) 53 68 
TaBLe B.—Apparent Length of Measuring Wires from Comparison 
with 480-foot Base. 
Date Wire 1 Wire 3 
1904 mm, min, 
May 26. 2 - 2438L-31L 
June 2. ; 4 F 24380°74 — 
pee 3 4 oa — 
ae NS . ij ‘ "75 — 
> Loi aes * : i ‘76 oe 
Ee ba ee ‘ ; 7 air —_ 
25 . = “15 — 
” . . 
The wire 3, used in previous bases, met with an accident on May 27; wire 1 was 
substituted. 
Each section of the base was measured three times, viz., once forward, 
then backward, finally forward. The results are given below. 
The separate lengths derived from each measurement are given 
below :— 
TaBLe C.—Measured Lengths of Sections of the Houts River Base, after 
correction, from comparison with Standard Base. 
Section mm, ) Section mm. 
418-1 4109 
5 5 - 1801+ 423-4 We = & . 1927— 4172 
437:0 4169 
[ 596 | 419°7 
i U gets 2 . 2007+ 60°6 VI. F P « 14474 411°6 
( + Co Ge 864-4 
TI, te ? . 1807+ ) 85:0 VII. is e « Li7l— 865°) 
87:7 859-2 
13622°7 5330°1 
EVGA 4 . - 2201 + Wilts x = » 1307— {su 
13621:7_ | 5334°4 
where /= 24380-'0mm. 
The measurements of the base line on the banks of the Loangwa, in 
Northern Rhodesia, are not yet definitively reduced. The base itself is 17,400 
métres in length ; the difference between the two measures was 49 milli- 
métres. 
As full details of all the base lines measured with the Troughton & 
Simms steel bars are given in Vol. i. of ‘The Geodetic Survey of South 
Africa,’ I need not go here into further detail, but merely state that their 
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