Judson (1909) listed nine factors that may 

 influence the currents of Lake Michigan but 

 concluded that the all-important one was the 

 wind. The winds and barometric pressure 

 produce currents that travel in any direction; 

 even in the Straits of Mackinaw the current 

 may flow either into Lake Huron or Lake 

 Michigan and vary greatly in velocity. (This 

 reverse flow in the Straits of Mackinaw was 

 observed by explorers as early as 1673.) 

 According to Judson, surface currents travel 

 a maximum of about 5 percent of the wind 

 speed up to 3 miles per hour and extend to 

 a depth of 30 to 40 feet. 



Barnard and Brewster (1909a and 1909b) 

 reported that local shore currents reach a 

 maximum distance of 5 miles from Michigan 

 City and at times beyond 10 miles from cer- 

 tain areas of the Indiana coast. These currents 

 flow in many directions according to the pre- 

 vailing winds. McLaughlin (1912) mentioned 

 winds and inshore currents but stated that 

 the prevailing current of Lake Michigan sweeps 

 southward into Grand Traverse Bay and moves 

 from west and east and then northward toward 

 the open lake. At times the currents reverse 

 from east to west. 



Townsend (1916) derived his paper from a 

 voluminous document of the House of Repre- 

 sentatives (No. 762, 63d. Congress, 2d. Ses- 

 sion) that included Great Lakes data on winds, 

 water levels, temperatures, and currents. 

 He pointed out that curvilinear surface cur- 

 rents illustrated by Harrington's map of Lake 

 Michigan were absurd because the 2 points of 

 a drift bottle's course could only represent 

 a straight line. No permanently defined cur- 

 rents are developed, he contended, because as 

 a rule they follow the direction of surface 

 winds and perhaps are affected by barometric 

 pressures. The currents may flow opposite 

 the wind when its intensity is low. Floats 

 deposited close to Wisconsin were recovered 

 on that shore, north or south of the release 

 point, whereas the floats released farther 

 out in the lake were driven by prevailing 

 westerly summer winds across to Michigan. 

 Eddies may develop but only in deep bays or 

 between extended points along the shore--not 

 along an unbroken shore. 



Shelford (1918) described the conditions in 

 Lake Michigan and among them referred to the 

 wave action that varied from depths up to 5 

 feet, the limit of sand-moving waves, to 26 

 feet; the limit of wave action is 82 feet. 



Horton and Grunsky (1927) also reported 

 that strong wind action and barometric pres- 

 sure increase the normal current in the 

 Straits of Mackinaw and at times reverse it 

 from Lake Huron into Lake Michigan. 



Crohurst and Veldee (1927) stated that no 

 constant or clearly defined water currents 

 exist in the Calumet region of Illinois and 

 Indiana. The movements vary continuously 

 with wind direction and velocity and should 

 be termed "wind drifts" rather than true 

 currents. Their observations with floats were 

 not useful. 



It is unfortunate that our 1931 and 1932 data 

 on the surface currents of Lake Michigan were 

 not recorded years ago. However, Deason 

 (1932) published a preliminary report of our 

 1931 program including records of five of our 

 interesting recoveries of drift bottles. A 

 short notice of the drift-bottle study of 1931 

 appeared in the U.S. Fisheries Service Bulle- 

 tin, No. 202, March 1, 1932. 



The limnological surveys of Lake Michigan 

 by the Bureau of Commercial Fisheries in 

 1954-56 and 1960 were briefly reported in the 

 Commercial Fisheries Reveiw. Several re- 

 ports showed the pattern and direction of 

 currents as indicated by drift cards. 



Smith (1956) described the release of 4,000 

 drift bottles in the northern half of Lake 

 Michigan in 1955. Nearly 60 percent of them 

 were returned by the end of the year. An 

 experiment indicated that the shortening of 

 wire between the drag and the bottle from 

 3 feet to 1 foot and the addition of a movable 

 brass ring at the neck of the bottle reduced 

 the loss of drags. In his 1957 paper Smith 

 reported a total of 6,300 drift bottles released 

 in the southern half of Lake Michigan in 1954 

 and in the northern half in 1955. 



Lauff (1957) released no drift bottles during 

 his 2-day survey of Grand Traverse Bay on 



