58 



DEPARTMENT OF THE NAVAL SERVICE 



8 GEORGE V, A. 1918 



Temperature and kind of weather at Long Beach Pond during the month of August, 



1915. 



August Mean average temperature of water =58 '9° 

 July Mean average temperature of water =58 09° 



Mean average temperature of air = 62'3° 

 Mean average temperature of air = 59 7°. 



On this subjiect the Rhode Island Commission remarks: — 



The temperature of the water is of paramount importance in order to 

 obtain the best results. Although it is possible to rear lobsters with some success 

 in cold water, the best results will be obtained with water at a temperature of 

 65° to Y5° F. This higher temperature results in a more rapid development of 

 the lobsters. This more rapid development results, first, in a reduction of the 

 expenses of operating the plant, because of the less time required, and, second, 

 in a greater proportion of fry reared to the fourth stage, because in the shorter 

 time there is less chance for death from cannibalism, parasites and injury. 



Prof. A. B. Macallum has suggested that, in order to overcome the handicap of 

 cold water, we should use sea-water that has been heated to 68° or 70°. This appears 

 to be a good suggestion, unless its adoption would increase to too great an extent the 

 cost of operating our plant. At a moderate calculation, about 2 cubic feet of water 

 per minute enters, and, of course, leaves each rearing box. To heat this quantity of 



