REVIEWS AND EXCHANGES 
89 
April 27. Against this day, in 1865, a temperature of 8i'5°is 
registered. This date is eighty-seven days before my Mid- 
summer-day, while that of the 81 ' in October is only seventy- 
three after. The first occurrence in the Summer of a mean 
temperature not below 60° is on June 13 (60-3°) ; but if we use 
the mean temperatures resulting from a great number of daily 
observations, this occurrence is deferred until the 21st (6o'8”). 
I think that many of the remarks contained in this article 
are conclusive as to the desirability of recognising a four-months’ 
Summer and a Winter of practically equal duration. A few of 
the statements may be a little irrelevant to the subject, but they 
have been allowed to stand on account of their extreme interest. 
REVIEWS AND EXCHANGES. 
Elementary Microscopy : a Handbook for Beginners. By K. Shillington Scales, 
F.R.M.S. Bailliere, Tindall and Co\. Price 3s. net. 
This little volume is precisely what its title represents it to be. It deals in 
a simple elementary way with the optics of the microscope, the choice of an 
instrument, its manipulation, and the mounting of objects, many pieces of appar- 
atus being illustrated. We are not sure whether the concise instructions given 
will suffice to make the careful student an expert microscopist without personal 
tuition ; but they will certainly put him in possession of the principles upon which 
his work must be based. In a future edition we hope room may be found for 
some reference to micro-photography and the microspectroscope. 
The Camera in the Fields : a Prcutical Guide to Nature Photography . By F. C. 
Snell. Fisher Unwin. Price 5s. 
In spite of the many beautifully illustrated books on the results of Nature- 
photography and the methods of stalking living animals for this purpose, there 
Toad. (From “The Camera in the Fields,” by kind permission of T. Fisher 
Unwin, Esq.) 
was, we think, room for such a manual as Mr. Snell has here given us. In the 
varied character and equal excellence of its eighty illustrations, including, as they 
do, charming bits of landscape, foreground, mammals, birds and their nests. 
