42 
POPULAR SCIENCE REVIEW. 
February . — The main characteristics of the January isotherms 
are again seen in the February chart; the temperature read- 
ings are shown gradually decreasing from the Scilly Islands 
(46°) to the north-east of Scotland (38°), while the same sharp 
angle southward is observable in many of the isotherms. But 
it will be noticed that, so far from the coldest region being now the 
coasts of the Moray Firth, a narrow band of still lower tempera- 
ture is shown stretching across south-eastern and central England. 
March . — This chart shows a general increase of warmth ; and 
this being greater Over central England than elsewhere, readings 
are more uniform, and the isotherms more regular. A small 
area of low temperature is, however, still shown over the northern 
and central parts of England, York having the same mean tem- 
perature as Stornoway and Wick, while the isotherm of 42° runs 
southward from Thurso through Aberdeen, Shields, &c., as far 
as Cambridge and Yarmouth. 
April. — The influence of the sea is beginning to be shown 
operating in the opposite way to that which we have observed 
in previous months, while the sun begins to exercise consider- 
able influence on the land. Scilly is not so hot as the mainland 
stations of Cork and Plymouth, while the comparative coldness 
of the northern islands is shown by the crowding together 
of the isotherms over the northern part of the mainland of 
Scotland. At the same time over that part of central England 
where formerly we found a cold region, the sun now possesses 
sufficient power to raise the day temperature to a height which 
produces a mean temperature superior to that of the surrounding 
districts. The more eastern parts of England are still cold, the 
isotherms having still a north and south direction on our east coast. 
May. — A further general rise of temperature occurs during 
this month, amounting, as a rule, to about 3°. Cork and Ply- 
mouth again show the maximum mean temperature, but the 
isotherms are not so crowded together in the north of Scotland. 
June. — A rise is shown over the whole country, the mean 
temperature now varying from 61° in the south to 53° in the 
north. Over the greater part of the country the increase is 
about 5°, but over central and southern England it amounts to 
as much as 8°. The hottest district is that around London, 
whence a narrow band of high readings extends northward over 
central England. It will be observed that all the isotherms 
send a narrow promontory northward over the central stations, 
showing the influence of the sun in raising the heat of the 
inland stations, and that of the sea in tempering the heat of 
the coast. 
July. — A further rise of 3° or 4° is shown ; but otherwise no 
great change has occurred, the relative distribution of the iso- 
therms being very similar to that of June. July is the hottest 
month in the year. 
