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HINTS TO TRAVELLERS. 
II. Inverse Process; to find the number corresponding to a given log. 
1. When the natural number is not required to consist of more than 
four figures, it is taken out at once. 
Example .—Given the log. 645820, required the natural number. 
The nearest log. in the Table is 645815; the figures at the side are 442, 
annexing to which that at the top, or 4, gives 4424, the number required. 
To place the decimal point. Add 1 to the given index of the log., and 
mark off to the left this number of figures; these will be whole numbers; 
the rest, if any, will be decimals. 
2. When the Number is to consist of five figures. Take out the next 
less log. to the one given, and note down the four figures of the corre¬ 
sponding number. Note the diff. D. 
Subtract this next less log. from the given one, and look for the 
remainder among the parts standing against D, in the lower part of the 
Table; note the figure at the top under which the remainder is found, 
and add it to the four taken out. 
3. When the Number is to consist of six figures, the more direct and 
accurate method is to take the diff. between the given log. and the next 
less in the Table, annex 2 ciphers, and divide by the diff. between the 
next less and the next greater; the quotient is the number of figures to 
be annexed to the natural number, answering to the next less log. 
Place the decimal point as previously directed. 
Example 1. (Five figs.) Find the No. to the log. 424471. 
Given .. ..424471 
Next less (2657) • • •• .. .. .. 424592 D. 164 
Rem. 79 
5tk fig. 4, next less. 66 
Numb, req. 26574 
Example 2. ( Six figs.) Find the No. to the log. 424471. 
Given log.424471 
Next less (2657) .. .. .. .. .. .. .. 424592 79 
Next greater .424555 165 
Then 7900-7-by i6j, gives 48, and the numb. req. is 265748. 
Table XXYI. Logarithmic Sines , Cosines , Tangents , Cotangents , Secants , 
and Cosecants.- —The Table contains the terms to half-minutes, and to six 
places. 
