114 Proceedings of the British Association. 



useful in regard to agricultural matters. For instance, we could 

 easily suppose a case of two portions of land, not many miles asunder, 

 but on different sides of a high range of hills, getting different 

 amounts of salt, from one being exposed to, and the others sheltered 

 from that wind in which the greatest amount was found. But by 

 this mode of collecting the rain, an accurate mode of estimating this 

 is within our reach. To the question, namely, the amount of solid 

 and gaseous matter brought in the rain from each direction, Mr. Knox, 

 hopes on a future occasion to turn his attention. 



The Tables which accompany this communication give the amount 

 of the rain corresponding to each wind, for each separate month in 

 the five years. The following are the yearly mean results, deduced 

 from the whole series. 



S. SW. W. NW. N. NE. E. SE. Total. 



6-548 10-639 6-034 2-789 2-352 2-172 2-251 3-173 35-958 



Mr. Dove said, that according to the hypothesis, that the meteoro- 

 logical phenomena of our latitudes may be explained by two currents, 

 a polar and an equatorial, which mutually replace each other, a dis- 

 tinction is to be drawn between two kinds of rain, the one caused by 

 refrigeration of the southern current coming into higher latitudes, the 

 other when the southern current in the place of observation is over- 

 powered and replaced by the northern. The first takes place when 

 the vane is SW., the latter when the vane passes from SW. through 

 W. to N., or from E. through S. to SW. The direction NE. indi- 

 cates the polar stream without condensation. Hence it follows, that 

 the quantity of rain is a maximum at SW., a minimum at NE., and is 

 distributed symmetrically on either side. 



The Bishop of Norwich expressed the satisfaction which he felt at 

 hearing the communication of Dr. Lloyd, and his hopes that extend- 

 ed series of similar observations would soon be put on record. The 

 great and anomalous varieties in the quantity of rain which fell in 

 various localities would, he had no doubt, be found such as to create 

 surprise. Thus, in London the quantity was only 23 inches annual- 

 ly, while in the neighbourhood of his residence it was no less than 

 33. — Sir John Herschel said that the importance of such observations 

 when well conducted, could scarcely be over estimated ; he believed 

 the discrepancy in the amount of rain which fell in several parts 



