Lake Maxinkuckee, Physical and Biological Survey 41 



soundings 3 people were employed, — one to row the boat, one to 

 operate the sounding machine, and one to record the readings. 



A smaller machine was sometimes used when sounding in shal- 

 low water. This consisted of a wooden reel cut out of a thoroughly 

 seasoned piece of oak and then boiled in oil and paraffin to pre- 

 vent splitting. This reel was just two feet in circumference, and 

 on its grooved rim was wound piano wire. A similar but lighter 

 sounding weight was used and the reel was installed in the boat 

 in essentially the same manner as was the larger one. 



Usually a sounding was taken at the end of every 15 oar strokes. 

 An effort was made to have the same person do all the rowing. 

 Before entering on the work he endeavored, through practice, to 

 acquire a uniform stroke, to the end that 15-oar-stroke intervals 

 between soundings might be approximately equal. 



Quiet days with little or no breeze and with the lake surface 

 undisturbed and smooth were selected for this work; under these 

 conditions the drifting of the boat was reduced to a minimum and 

 it was easy to follow a definite line. In order to do this, range 

 signals were placed on shore; these were always visible to the 

 rower. 



Lines of soundings were run across the lake on all section, half- 

 section and quarter-section lines, both east and west and north and 

 south, and in a number of places lines were run at even closer 

 distances. 



In order to determine the location and extent of bars, deep 

 holes, or other topographic features of special interest, a buoy was 

 established on the bar or other special feature, from which radi- 

 ating lines of soundings were run in sufficient number and with 

 the soundings at sufficiently short intervals to determine the de- 

 sired facts. The locations of these buoys were determined by 

 sextant readings based on shore marks of known position. 



During the winter of 1900-1901, a number of lines including 

 several hundred soundings were run by Mr. Clark when the lake 

 was covered with ice. The exact position of each of these sound- 

 ings was determined from known shore positions by measure- 

 ments on the ice. 



It is believed that the care taken at all times while carrying 

 on this work, the great number of soundings taken, and the fre- 

 quent verification of questionable results, justify the belief that 

 the hydrography of this lake has been pretty accurately deter- 

 mined and that the contour lines on the map showing the depths 

 may be depended upon as showing the actual depths with reason- 

 able accuracy. 



