SCIENTIFIC WEATHER FORECASTING. 5 



tance and then trying to get out the resultant velocity of 

 the wind. 



All this be it remembered was published in 1820, and 

 therefore was probably done some years before. In 1830 

 Redfield in the United States announced that (i.) storms were 

 approximately circular (ii.) travelled north-eastwards (iii.) 

 increased in strength towards the centre ; but (iv.) became 

 calm at the centre, and he illustrated this by a diagram (6). 



FVom about 1830, Col. (afterwards Sir Wm.) Reid was 

 at Bermuda, and in his Lazo of Storms (7) he says : — 



" A very interesting mode of testing the Law of Storms 

 is that of considering the probable line of progression of 

 gales in their passage. It was thus that I (Col. Reid) was 

 in the habit of studying the winds at Bermuda for nearly 

 eight years, and that Mr. Redfield has studied them at New 

 York for a much longer period. In September, 1839, Mr. 

 Redfield wrote to me from New York, when he first heard 

 of the gale of that year, that he thought it must have passed 

 over Bermuda ; and this was before he could have heard 

 from these islands. A reference to the plate will show how 

 correct his judgment was, for the centre touched the wester- 

 most part of the islands." 



From 1830 onwards, the construction of weather maps 

 was general with leading meteorologists, such as Espy, 

 Piddington, Redfield and Reid ; but these, it must be re- 

 membered, all referred to dates far anterior to their con- 

 struction. The electric telegraph was not invented until 

 1837, and it was not until a much later date that its use was 

 sufficiently extensive and cheap to allow meteorologists to 

 avail themselves of it. 



The first proposal for the use of the telegraph, and of 

 synchronous observations for weather forecasting, which we 

 can trace, was by Carl Kreil in 1842, when he was assistant 

 at Prague Observatory (8). It is much too long for repro- 

 duction, but points out the necessity for having distant 

 stations ; that the optical telegraph was scarcely sufficiently 

 rapid and could not be used at night, but that the recently 

 discovered electro-magnetic telegraph, as soon as it had 

 been brought into general use, would precisely meet the 

 case, and he illustrates the method by the passage of the 



