44 Proceedings of the Royul Physical Socicty. 
than the mean temperature itself. During June the mean 
daily range averages 14°5 (at Greenwich, 21°2); in July, 
12°9 (Greenwich, 21°°0); in August, 12°:1 (Greenwich, 
20°-3). It follows that the average difference between night 
TABLE II].—Mcan Temperature of the Seasons. 
Strathpeffer, ee Difference. 
| Winter (December to February), . | 37°0 | 37-4 ~0°4 
| Spring (March to May), P ‘ APG.) oy 440 ~4-4 
| Summer (June to August), ; 55°1 61°6 —6°5 
Autumn (September to November), 459 49°7 -3'8 
| Waa VES Marek | eee 413 9 ~ 35 
and day temperatures for the summer is 13°:2 at Strathpeffer 
against 20°°8 at London. The comparatively small daily range 
in the northern summer is, of course, owing to the relative 
coolness of the days, which, again, has been attributed to the 
influence of the sea, coupled with the free circulation of air 
on the hill-sides.1 It is worthy of notice that, while the 
average day temperature falls about ten degrees below that 
of London, the corresponding difference between the night 
temperatures is only a little more than two degrees. 
Winter Temperature—We have just seen that the Strath- 
peffer summer is between six and seven degrees cooler than 
at Greenwich. The winter temperature presents a striking 
contrast, being, on the average of observations, within half a 
degree of that of London. The tendency, already noticed in 
the case of the summer months, to a comparative warmth of 
the night and a small daily range is still more marked in 
winter. This is shown in Table 1V., which gives the average 
maximum, minimum, and mean temperatures for the seven 
winters from 1884-91. With regard to the minima, it appears 
1 See Strathpeffer Spa, its Climate and Waters, chap. ii. (by H. Courtenay 
Fox, late F.R.Met.Soc., to whom I am indebted for valuable aid in 
preparing this paper). 
