INDEX. 
435 
IX. Distance of the sea-horizon un¬ 
corrected for effects of refraction, 253 ; 
explanation, 221 
X. Reduction to the meridian for 
latitude observations, values of, 
2 Sin 2 b hour — 
Sin 1"- > 254-255; explana¬ 
tion, 221 
XI. Geographical miles, or minutes 
of the Equator, contained in a degree 
of longitude under each parallel of 
latitude, with a compression of g J ? , 
256; explanation, 222 
XII. Conversion of statute into geo¬ 
graphical miles,257 ; explanation, 222 
XIII. Conversion of geographicalinto 
statute miles, 258 ; explanation, 222 
XIV. Comparison of thermometer 
scales, 259; explanation, 222 
XV. Conversion of English inches 
and tenths into millimetres, 260 ; ex¬ 
planation, 222 
XVI. Conversion of metres into 
English feet, 261-265 ; explanation, 
222 
XVII. Conversion of kilometres into 
English statute miles, 266 ; explana¬ 
tion, 222 
XVIII. Conversion of versts into 
English statute miles, 267; explana¬ 
tion, 222 
XIX. Conversion of kilogrammes 
into pounds avoirdupois, 269; explana¬ 
tion, 258 
XX. Foreign moneys with equi¬ 
valents in British currency, 268 ; ex¬ 
planation, 222 
XXI. Traverse table, 269-277 ; ex¬ 
planation, 222 
XXII. Table to correct for irregu¬ 
larity of moon’s motion to be used in 
finding longitude by moon culminating 
stars, 278-279; explanation, 222 
XXIII. Angles subtended by a 10-ft. 
rod at distances from 50 to 1500 ft., 
table, 280-281; explanation, 222 
XXIV. Useful constants and num¬ 
bers, 282-283 
XXV. Logarithms of numbers, table, 
284-301 ; explanation, 223 
XXVI. Logarithmic sines, cosines, 
tangents, cotangents, secants, and co¬ 
secants, table, 302-391; explanation, 
224-228 
XXVII. Proportional logarithms, 
table, 392-406 ; explanation, 228 
XXVIII. Natural cosines, table, 
407-421; explanation, 229 
XXIX. Arc into time, table, 422 ; 
explanation, 230 
XXX. Time into arc, table, 422; 
explanation, 230 
XXXI. Acceleration table, 423 ; ex¬ 
planation, 230 
XXXII. Retardation table, 423 ; ex¬ 
planation, 230 
XXXIII. Parallax in altitude of a 
planet, table, 424; explanation, 230 
XXXIV. Correction of the moon’s 
equatorial horizontal parallax for the 
figure of the earth, table, 424 ; expla¬ 
nation, 230 
XXXV. Reduction of latitude, com¬ 
pression g J 0 , table, 425; explanation, 
231 
XXXVI. Augmentation of the 
moon’s semi-diameter, table, 425 ; ex¬ 
planation, 231 
Tacheometer, description and illustration 
of, 35-36 ; principle of measuring dis¬ 
tances with, how to find the value of 
micrometer divisions, must be set at 
solar focus, 37 
Tacheometer surveying, principle of, 75 ; 
article on surveying with the, 111-113 
Tanner, Col. H. C. B., his paper on bar- 
subtense survey, 113-116 
Tape, measuring, 3, 5 
Telescope for occultations, & c., 8 
Telescope level of transit theodolite, 
adjustment of the, 28 
Telescope observations, list of, 136 
