Abraham Follett Osier. 331 



At a later period, when he had made improvements in the details 

 and construction of his anemometer, he simplified the mileage record 

 by using a double cam that caused a pencil to rise and fall at speeds 

 proportionate to the velocity of the wind, upon the paper moved by 

 the clock, thus getting the curves of pressure, direction, velocity, and 

 rainfall, in connection with time, recorded on the same sheet of paper. 



Papers were read by Mr. Osier before the British Association, in 

 1839, at Birmingham ; and in the year 1840 he gave one at Glasgow, 

 in which he developed a method of exhibiting the relative prevalent 

 and intensity of winds from different directions by so-called " wind 

 stars," afterwards adopted by Capt. Fitzroy. These wind stars depict 

 the proportionate amount of wind from each of sixteen points of the 

 compass during a given period ; he further made suggestions of apply- 

 ing this graphic method to observations of temperature, atmospheric 

 pressure, and rainfall, which were afterwards followed up by Prof. John 

 Phillips, whose very valuable results were given later, in 1846. 



Mr. Osier also developed another series of monthly, quarterly, 

 annual, and mean diurnal wind curves, which clearly illustrated the 

 average distribution of winds during each part of the day, and for the 

 different seasons. In these curves he noticed that the periods of calm 

 came generally after midnight, and the periods of greatest disturbance 

 after mid-day. 



This observation led him to place mean diurnal wind velocity curves 

 parallel to the mean diurnal temperature curve, and he found that, on 

 reducing the two maxima and minima to the same values, they became 

 almost identical. 



Sir David Brewster, in a paper read at the same meeting, 1840, on 

 " Barometric oscillations at Inverness," came to the same conclusion, 

 and, referring to the outcome of his barometric and thermometric 

 observations, made use of the following words : " This very important 

 and new result is confirmed in a remarkable manner by the observa- 

 tions of Mr. Osier at Birmingham, made at the request and expense of 

 the British Association, which I have seen since I arrived at Glasgow 

 observations of inestimable value, which exhibit more important results 

 respecting the phenomena and laws of the wind than any which have 

 been obtained since meteorology became one of the physical sciences." 



Mr. Osier often strongly urged the necessity of establishing meteoro- 

 logical observatories at suitably selected stations in different latitudes, 

 so that aerial movements could be examined in tropical regions, where 

 the action of the sun, as the great disturbing cause, is more marked, 

 and its results more simple and regular, and also at a series of 

 stations extending through the temperate zones, where the conditions 

 become more complex. He maintained that if all these observations 



