[ <6 7 
30 minutes, which reduced to minutes and divided by 22, the 
quotient is 12 minutes 16 feconds, 
Now I will try what the analogy refpecting Mr. Kendrick’s 
date will produce. 
, : Vid 
12 20 PR INS: RE ye 
t 
So that early in the year 1745 the variation muft have been 
18 degrees wefterly. 
‘Last y, to prove, by the ratio, that the variation was 19 ~ 
degrees in the year 1750, 
From 1750 
Take 1657 
—— 
93 remains. 
——— 
Multiply 12 minutes 20 feconds or 740 by 93, the product is 
68820 feconds, which reduced is 191 degrees : fome time therefore 
in the year 1750, I conclude, the variation was 19 degrees wefterly, 
and not in 1751 or 1752, as Mr. Gibfon has noted it, and confe- 
quently it could not be fo in 1753, when Mr. Kendrick, the City 
Surveyor, fanttioned it with the authority of his name. I fpeak thus, 
to excite every perfon concerned in maps of a public nature (in 
 fhort either public or private) to care and attention. An omiffion. 
of the meafure of the variation of the needle, efpecially in exten- 
five maps of any part of the country, is very reprehenfible, 
becaufe the boundaries may be fo defaced that the oldeft man 
living 
