AQUATIC LIFE I3I 



The carbon dioxide content of the water was determined by 

 titration. On the seat in the stern of the boat was carried a case 

 which contained all the requisites for making the analysis of 

 carbon dioxide content. It contained a small bottle of indicator 

 to which was attached a tube with a spring clamp which kept the 

 bottle air tight and facilitated the using of the indicator. Another 

 bottle similarly equipped contained sodium hydroxide. A test 

 bottle was lowered to the bottom of the Cove by means of a long, 

 stout cord. To the neck of this bottle a weight, heavy enough to 

 Submerge it, was attached. To the cork was fastened a stout cord 

 by means of which the water-tight bottle could be opened after it 

 had reached the desired depth. The carbon dioxide content was 

 taken as follows: the test bottle was made as free from air as our 

 means would permit and the stringed-cork tightly inserted. The 

 bottle with weight and cord attached was lowered into the water 

 to the desired depth and the stringed-cork was pulled allowing the 

 water to enter until the bottle was completely filled. Then it was 

 drawn gradually to the surface and corked to keep the air from 

 entering. Before the titration was made the top portion was 

 quickly poured off to obtain more accurate results and looo c. c. 

 taken from the remainder. To this a few drops of indicator was 

 added drop by drop and the number of c. c. required to color the 

 solution a delicate pink determined the amount of carbon dioxide 

 present in looo c. c. of water. On a following page the results are 

 given. These readings were made only on two trips owing to the 

 amount of time it required to make them and to the fact that the 

 presence of the carbon .dioxide was practically constant for the 

 length of time we were working on this problem. 



All temperatures were taken by means of an accurately 

 adjusted and tested deep sea thermometer. Four readings^ were 

 taken at the nine stations every trip; air and water temperature 

 at the surface, water temperature one half distance to the bottom, 

 and on the bottom. 



The turbidity was taken by the use of a \ ery simply constructed 

 turbidimiter made of a Mason jar cover in the top of which was 

 the customary porcelain disc. To the sides to this coveir were 

 attached three strings which were tied at a point 4 inches above 

 the cover. This method of attachment kept tlie white porcelain 

 disc parallel to the surface. From the three strings extended a 

 long extension which was used. for law.ering.the cover, from the 



