26 REPORT—1849. 
atmosphere, being put in motion and carried on by momentum previously acquired, 
causing great undulations in its motion, on which occasions the wind appears to 
have much more force than is really indicated by an instrument. The north winds 
generally showed less oscillation than those from the south points. While carrying 
on these observations, Mr. Osler’s attention had occasionally been directed to par- 
ticular storms, and he had applied to them the rotatory theory set forth by Colonel 
-Reid, in the main principles of which he fully agreed; but he considered that a 
rotating circle would not explain all the changes that occur. He was of opinion 
that the rotating portion is smaller than has usually been assumed, and that the 
air approaches this circle or vortex in spiral lines; that sometimes this rotating 
circle is not in contact with the earth, in which case the lower current will be more 
in the direction of radial lines; that the air in advance of a storm is not put into 
such rapid motion in consequence of the movement forward of the storm itself, while, 
for the same reason, the action in the rear of the storm is increased. 
Mr. Osler called the attention of the Section to the great practical importance of 
endeavouring to ascertain the exact course of the wind in rotatory storms, which he 
considered might be done with the aid of the instruments we now possess. The 
Americans were beginning to take the subject up in a manner worthy of its import- 
ance; and Mr. Osler hoped that while Lieut. Maury and others were at work on 
the west coast of the Atlantic we should take the east. He recommended that a 
series of stations for meteorological observations be established, commencing at the 
Canaries and including Madeira and Gibraltar, the west coast of Spain and Portugal, 
the Azores, Guernsey, &c. In England, Ireland and Scotland many stations are 
already established that would no doubt join in contributing observations. By 
adopting a well-organized and comprehensive system, the main currents on the east 
of the Atlantic might soon be ascertained with great exactness. 
Mr. Osler then exhibited and described his improved integrating anemometer. A 
plain sheet of paper, about twelve inches wide, and long enough to last some weeks 
(or months if required), is first rolled on a cylinder whose axis is horizontal, and 
passing over a second cylinder is received on to a third. Over the central cylinder is 
placed a registering pencil. The second and central cylinder is made to revolve in 
proportion to the rate at which the air is passing, by means of rotators exposed to 
the atmosphere. The direction is obtained by the same means that Mr. Osler 
adopted with the anemometer at Lloyd’s, and which is found to act with great 
exactness, laying down the direction in a single line free from all oscillations. This 
is accomplished by means of a fan-sail, similar to that at the back of a windmill, 
the motion from which is conveyed to a pencil. The paper is ruled as it passes on, 
by means of pencils indicating the direction. The time is recorded by a clock, 
which causes a series of small punches marked with the hour to be brought round — 
in succession, one of which receives a blow every hour from the hammer of the 
clock, and records it on the margin of the paper. Thus a single line gives the di- — 
rection and quantity of air passing any station, while every hour the clock marks 
off the time. Mr. Osler pointed out some improvements he had made in his original _ 
pressure anemometer, by which he was now enabled to record the force of even — 
light winds at the same time the instrument was strong enough to resist storms. 
In conclusion, Mr. Osler said that he had long been impressed with the conviction, — 
that if greater attention were paid to a study of the currents of the atmosphere, it 
would prove to be of more importance in advancing the science of meteorology than ~ 
anything else that has hitherto been done. It was this conviction that led him to — 
construct his first anemometer in 1836; and though he was not so sanguine as to 
expect to see meteorology vie with astronomy in its mathematical prophecies, yet he — 
believed that if the subject were taken up on a systematic plan for a short period 
the results might prove of very great value to science. 

On the Temperature of the British Isles, and its influence on the Distribution 
of Plants. By Aucustus Perermann, F.R.G.S. 
The author adverted to the climate of Western Europe as being the mildest, 
comparatively, of all countries in a similar latitude, and showed that a temperate 
zone, limited by the isothermals of 70° and 30° (Fahr.), extended in 



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