Letter from Frank F. Wood to Increase Allen Lapham, September 18th

US Signal Office
Grand Haven Mich
Sept 18 1871

Prof. I. A. Lapham

Sir
Your communication of the 14th
inst came to hand this morning, in reply I would
say, the elevation of this station is 612 ft, calling
Lake Michigan 583 ft above the sea, height of ground
on which office stands 16 ft above Lake, height of
cistern of Barometer above ground 13ft total 612ft

The elevation of Lake Michigan as put down
in my instructions is 583 ft.

Very Respectfully
Frank F. Wood
Obs Srgt S. S. U.S.A

Lake Michigan should be 578
Hence Grand Haven Bar 607

Lake Mich 578
Ground 16
Instrument 13
Barom 607