p.2

Each observer should have a
special table to reductions to the sea
level, adapted to the elevation & the range
of temperature & pressure at his station.
This would save time, prevent errors, &
secure uniformity which is all-important.

The table in Loomis will soon be worn out
by constant use. Some observers
use the mean temperature of the month --- others
the temperature at the time of making
the observation.

I a L

Nov. 21

Sent to Gen Myer at
Washington
Nov 21st 1870

Memoranda
Sent to Gen A. J. Myer
Nov 21 1870