Page:Polar Exploration - Bruce - 1911.djvu/209

Rh the lowest reading of the quarter thermometers. Furthermore, when the Scotia was wintering in Scotia Bay, and when there was a regular series of meteorological instruments set up in thorough observatory fashion ashore, it was found that the weather-side deck thermometers compared absolutely with those on shore.

"Except on rare occasions," says Mr. Mossman, "one side of the ship was definitely a weather and the other a lee side. It may be worthy of notice that there was usually a difference of one or two degrees between the weather and the lee side of the Scotia, the instrumental readings on the lee side being affected by heated currents from the cabins and engine-room,—hence the importance of having thermometer screens on both sides of the poop. On one occasion the lee side was as much as 5° warmer than the weather side, and on another occasion, during a calm, a difference of nearly 10° was noted."

A further check was afforded by the records of three Richard thermographs, which gave continuous records of temperature. Some little trouble was at first experienced by Mossman with the wet bulb thermometers, due to saline accretions on the muslin and bulb of the instrument, such as are formed on every exposed part of a vessel at sea. The result was that in the course of a week or so a coating of salt