It is half-past eleven before he peeps over a small ridge of hills opposite to the house, and he sinks in the horizon at half-past two.

On the 28th Mr.Hood, in order to attain an approximation to the quantity of terrestrial refraction, observed the sun's meridian altitude when the thermometer stood at 46 degrees below zero, at the imminent hazard of having his fingers frozen.
He found the sextant had changed its error considerably, and that the glasses had lost their parallelism from the contraction of the brass.

In measuring the error he perceived that the diameter of the sun's image was considerably short of twice the semi-diameter, a proof of the uncertainty of celestial observations made during these intense frosts.

The results of this and another similar observation are given in the footnote.* (*Footnote.

The observed meridian altitude of sun upper limb was 2 degrees 52 minutes 51 seconds.