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northern icedrift — the consequence of which you will feel hi England and 
other northern countries. The enormous iceblocks will be drifted into the 
Atlantic, and, melting there, will be the cause of much rain, hail, and snow, 
with a considerable lowering of your mean summer temperature.” 
Causes and Conditions of Rain. ■ — M. Eenou, the distinguished French 
meteorologist, has put forward his opinions on the subject of the cause of rain, 
and although his views do not differ materially from those of other meteorolo- 
gists, they express a useful summary of the causes which produce rain. 
Eain depends on the following circumstances : — (1.) Elevation of temperature. 
(2.) Humidity of the air. (3.) Barometric depression. (4.) Variation of 
temperature. (5.) General conformation of the earth’s surface. But all these 
conditions may modify each other materially as follows: — (1.) Eain increases 
with the temperature, because hot air dissolves more water than cold air. (2.) 
The moisture of the air, which attains a maximum at the sea-shore, tends to 
produce a maximum of rain. This cause being constant, whilst the circum- 
stances which tend to produce rain in the atmosphere being present to the 
slightest extent, rain is frequent, especially small showers, and storms are 
rare. (3.) In proportion as the mercury falls, there is more chance of rain 
being formed. Inversely, in countries with a high barometric pressure, such 
as those in the 30th degree of latitude possess, there is little prospect of rain. 
Such regions have a tendency to become deserts. (4.) Variations of tempera- 
ture and irregularities of climate increase the chances of rain. (5.) Finally, 
the form of the soil plays an important part in the production of rain. An 
ascending concave soil receives a maximum of rain when it is exposed to rainy 
winds. — Vide Comptes Rendus, April 9. 
Influence of Wooded Districts in the Production of Rain. — M. Becquerel and 
his son have laid before the French Academy the results of several observa- 
tions conducted in the environment of Montargis. The general conclusion 
which the authors arrive at is, that wooded districts draw down a 
larger quantity of rain that plains do. They say it is of importance to- 
remember the fact that when the clouds approach a mountain, or even a 
simple hill, they ascend, and then, meeting a colder stratum of air, be- 
come converted into rain. Hence one is led to think that lofty woods may 
have a similar effect, and may thus materially modify the local climate of a 
district. To put this view to the test, say the authors, we have, with the 
assistance of the Academy, established five observatories in the district of 
Montargis, at each of which, since July last, a daily record is kept of the 
temperature of the air and the earth, and of the rainfall in districts thickly 
planted. The result of the observations conducted up to the present time has 
proved that far more rain falls in the wooded than in the unwooded districts. 
St. Flmoh Fire. — A good account of this curious phenomenon has been 
given by Captain Briggs, of the steamer Talbot , who observed it on the 7th of 
March, in the Irish Channel, at about one o’clock in the morning. He gives 
the subjoined description of his experiences : — “ I found,” he says, “ that the 
light, which appeared large at a distance, was made up of a number of jets, 
each of which, expanded to the size of half-a-crown, appeared of a beautiful 
violet colour, and made a slight hissing noise. Placing my hand in contact 
with one of the jets, a sensible warmth was felt, and three jets attached them- 
selves to as many fingers, but I could observe no smell whatever. The jets 
