94 ANNUAL RECORD OF SCIENCE AND INDUSTRY. 



compact column. At times, twenty or thirty of these col- 

 umns can be counted. A bluish steam accompanies the 

 eruption, which rises straight into the air with great power, 

 from many hundreds of fathoms. 



In connection with this eruption, it is interesting to notice 

 that during the nights of March 29 and 30 a heavy rain of 

 ashes or sand took place along the west coast of Norway 

 to the Swedish frontier, the whole country being covered 

 with gray dust to such an extent that from a pint of snow 

 more than a tablespoonful of residue was left after the snow 

 had melted. The dust consisted of little irregular sharp- 

 edged grains, principally silicates, and probably originated 

 from the eruption in Iceland. 12 A, XII., 75, and XL, 575. 



DRYNESS OF THE SOIL IN INDIA. 



In a memoir on the waterworks at Nagpur, Central India, 

 Mr. Binnie gives a large amount of information with refer- 

 ence to the variability of the rainfall in India and other coun- 

 tries; and among the investigations into which he entered 

 was one illustrating the dryness of the soil during the dry 

 seasons, and the consequent amount of water absorbed by it 

 after every rainfall. An area of 6 T 6 o square miles, or 4224 

 acres, was drained by trenches into a reservoir, and the 

 height of water in the latter subjected to careful observa- 

 tion. Three rain-gauges were also placed within this area, 

 by means of which the rainfall could be determined. It was 

 found that in the case of a measured fall of 2.24 inches of 

 rain which fell in one hour and twenty minutes on the 18th 

 of June, there was no perceptible drainage from this area 

 into the reservoir, while on the 16th of September, in the 

 case of a rain of 2.2 inches, which also fell in one hour and 

 twenty minutes, the drainage into the reservoir amounted 

 to over 33,000,000 cubic feet. These opposite results prove 

 the extreme state of dryness of the soil in India at the end 

 of the heated season, and its complete saturation after the 

 heavy rains of the monsoon period. Of the drainage ob- 

 served on the 16th of September, 98 per cent, entered the 

 reservoir within two hours and fifty minutes. As to the 

 question what percentage of total annual rainfall drains 

 from the ground and can be emptied into reservoirs, Binnie 

 states that almost every drainage area has, in this respect, 



