SEA-FISHERIES LABORATORY. 227 



23rd) the temperatures varied from 1T2° C. to 178° C., 

 and the salinities from 1018 to 10276, the latter 

 reading being a high salinity for British seas. It was 

 recorded on August 12th in the open sea to the east of 

 the Shetlands, but nearly as high a reading was obtained 

 off Fair Island, off North Ronaldsay, and elsewhere in the 

 Orkney seas, and 1027 was obtained on July 13th and 

 14th off Canna and Rum on the west of Scotland. 



Physical Observations. 



The full list of our observations on temperature and 

 salinities is appended to this paper. The list gives 

 the dates, localities and times of the observations, 

 the temperatures Centigrade, as taken in a cooled, clean 

 canvas ship's bucket, rinsed and dipped from the forward 

 part of the ship, and tested with the thermometer without 

 delay. The next column gives the observations as taken 

 at the time with a Kiel araometer immersed in a cylinder 

 of the same water from the bucket, the cylinder having 

 been rinsed with a sample of the water before being filled. 

 The sixth column gives the specific gravities at 17'5° C, 

 as a result of reducing these readings at the given 

 temperatures by means of Knudsen's Hydrographical 

 Tables. 



On looking at the first column in the list it is clear 

 that some of the temperatures are merely due to temporary 

 conditions of the locality — such as 17'8° C. at Loch 

 Scavaig, in Skye, at 10.30 p.m., after a hot calm day, 

 when the high temperature was no doubt due to the effect 

 of the sun on the neighbouring rocks during the afternoon. 

 On the other hand, several of the series of temperatures 

 clearly indicate tracts of colder water. For example, in 

 the North Channel and round the Mull of Cantyre, our 

 readings lie between 11° and 12°, which is lower than the 



