p.1

Duluth, Minn
Nov 16th 1870

Sir

Your communication was received to
night. I have followed your instructions, and
complied with request. I do not correct the
observed heights of Barometer, only in my
weekly reports by mail, as printed directions
inform me, I will refer you to this, part-" viz
These deductions will in all cases be made
before the observations are transmitted by
telegraph, or entered on the fifth column of
form (four) 4. I took the latter method, why
I will explain in another letter, I will give
you, the observed heights, and the way. I
made my corrections, if not correct, please
give me a plain explanation of the method
in making reductions, and I will be obliged,

Observed heights

10th 29, 45
11th 29, 24
12th 29,21

alt sher

10th 46
11th 43
12th 53

Instrumental
Error
008
to be subtracted

Numbers taken from temperature

10th lt, 046
11th lt, 038
12th lt, 064

amount
addes for sen
level
10th 743
11th 732
12th 723