Stations were numbered consecutively through- 

 out the operating period each year and usually when 

 a station was visited more than once in a year it 

 retained its original number. As a rule, hydro- 

 graphic stations were established at fishing loca- 

 tions, and at intervals between fishing stations and 

 ports of call as time and conditions permitted. Tem- 

 perature records at hydrographic stations were made 

 with bathythermographs and with reversing thermom- 

 eters attached to Nansen bottles. Surface tempera- 

 tures were determined by lowering a resistance- 

 thermometer bulb just below the surface beside the 

 ship or by immersing it in a bucket of freshly col- 

 lected lake water. After Cruise II of 1953, surface 

 temperatures were also taken from a resistance- 

 thermometer bulb inserted in the ship's sea chest 

 which has an intake about 5 feet below the waterline. 



Water for chemical analysis was collected with 

 Nansen bottles. Sampling depths varied according 

 to the temperature profile. When the water was 

 homothermous samples were taken at the surface and 

 bottom, and sometimes at intermediate levels de- 

 pending on the depth. In areas of thermal stratifi- 

 cation, samples were collected at the surface and 

 bottom, and in the vicinity of and below the meta- 

 limnion. 



Secchi-disc readings, surface-plankton tows, 

 and a sample of bottom fauna were usually taken at 

 each hydrographic station. Bottom fauna samples 

 and bathythermograph casts were usually made in 

 connection with fishing operations. 



Bathythermograph casts were made at approxi- 

 mately 5-mile intervals between ports and between 

 fishing and hydrographic stations. After Cruise II, 

 1953, surface-water samples for chemical analysis 

 were usually collected with each bathythermograph 

 cast. These samples were collected with a clean 

 galvanized bucket that was used for no other purpose, 

 and care was taken in filling sample bottles to avoid 

 contamination. 



"Drift cards" (postal reply cards sealed in poly- 

 ethylene envelopes) were released at a few selected 

 stations during Cruise IV, 1953. Limited studies in 

 Green Bay, Lake Michigan, in 1952 revealed that 



only a small percentage recovery could be expected, 

 so single releases of about 500 to 1, 000 cards were 

 made at one location. 



Meteorological conditions were recorded rou- 

 tinely at frequent intervals in the ship's log, and on 

 station log sheets each time a hydrographic or fish- 

 ing station was visited. Observations included wind 

 direction and velocity, sea state, barometric pressure, 

 sky cover, visibility, and general weather conditions 

 (table 1). Data on wind direction and velocity are 

 approximate, since an anemometer was not used. 



Investigations conducted with the Cisco were 

 under the general supervision of James W. Moffett, 

 Chief, and Ralph Hile, Assistant Chief, of the Great 

 Lakes Fishery Investigations, U. S. Fish and Wildlife 

 Service. Vessel operations were supervised by Stanford 

 H. Smith. Paul H. Eschmeyer planned the lake trout 

 study and assisted materially in organizing other phases 

 of the Lake Superior program. 



Vernon Seaman served as captain of the Cisco 

 in 1952 and during Cruises I and II, 1953. Leo F. 

 Erkkila acted as captain-biologist in Cruise III, 1953, 

 and Clifford L. Tetzloff served in this capacity during 

 subsequent cruises. Clifford LaLonde was engineer 

 and John Blanchard fisherman-deckhand during the 

 entire operation. 



Paul H. Eschmeyer, Stanford H. Smith, and 

 LaRue Wells were in charge of field operations dur- 

 ing different cruises. Others who served as scientists 

 aboard the Ci^co in Lake Superior were Joseph Beil, 

 Howard Buettner, Daniel Garn, Willis Glidden, 

 Carl Jacoby, and Richard Ryder. 



Several people from other organizations gave 

 valuable assistance in addition to undertaking special 

 studies of their own. Russel Daly of the Wisconsin 

 Conservation Department served on the vessel to col- 

 lect data on smelt of the Apostle Island area during 

 parts of Cruises n and V, 1953. James H. Zumberge 

 (Cruises V and VII, 1953), and James T. Wilson 

 (Cruise VII, 1953) of the Department of Geology, 

 University of Michigan, conducted exploratory core 

 sampling and underwater photography from the Cisco . 

 William Hazen made special plankton collections 



