MICHIGAN ACADEMY OF SCIENCE. 
41 
The following members of the 
engaged in the field work: 
United States Geological Survey were 
Topugra phic Merpp i ruj : 
J. IT. Jennings, Geographer. 
A. M. Walker, Topographic Engineer. 
L. L. Lee, Assistant Topographer. 
Fred Graft’. Jr., Assistant Topographer. 
II. W. Peabody, Assistant Topographer. 
L. I>. Townsend, Junior Topographer. 
X. E. Ra Miner, Junior Topographer. 
C. R. French, Junior Topographer. 
('. W. Howell, Topographic Aid. 
Pi imary Traverse: 
J. R. Ellis, Topographer. 
J. 11. Wilson, Junior Topographer. 
Levels: 
L. 1). Townsend, Junior Topographer. 
J. J, McNulta, Topographic Aid. 
F. J. Mabrey, Topographic Aid. 
C. E. A f i 1 Ls , Topographic Aid. 
OFFICE WORK. 
The office drafting of the Lansing sheet was completed and trans- 
mitted for engraving, April J, 1911. The drafting of the Grand Rapids 
sheer was commenced, twelve per cent being completed December 31, 
1911. 
The adjustment of the levels for the Grand Rapids quadrangle, fur- 
nishing complete vertical control, has been made and the field notes 
typewritten and prepared for publication. Partial vertical control for 
the Holland, Ionia. Jenison, Lowell, and Muir area has been adjusted 
and the results typewritten and prepared for publication. 
The final computations for the geographic positions furnishing com- 
plete control for the Swanton quadrangle have been made and the re- 
sults typewritten and prepared for publication. Preliminary computa- 
tions for the geographic positions in the Grand Rapids area have been 
made. Partial horizontal control for the Adrian, Alvordton, Rlissfield, 
Hillsdale, Hudson, and Reading quadrangles has been furnished by the 
computation of geographic positions, which results have been prepared 
for publication. A preliminary adjustment of the traverse line fur- 
nishing partial horizontal control for the Allegan, Cedar Springs, 
Centerville, Charlotte, Gobleville, Hastings, Ionia, Jenison, Jones, Kala- 
mazoo, Lowell, Marcel lus, Muir, Schoolcraft, Vermontville, and Way land 
quadrangles has been made, but final adjustment not yet completed. 
