260 ANNUAL OF SCIENTIFIC DISCOVERY. 



quotient 175, being the 1 number of years requisite to exhaust the sup- 

 ply of water at the rate of 10,000,000 cubic metres per day! This 

 would be correct, supposing the quantity of water to remain station- 

 ary, and never to receive any increment by the infiltration of rain- 

 water and that of rivers. This M. Gaudin calculates at half a metre 

 per annum, and thence arrives at the conclusion that the annual in- 

 crease of the water is double the quantity expended ; so that the arte- 

 sian wells in or about Paris are and must ever be inexhaustible. 



Artesian Wells in tlie Desert of Sahara. The Paris Cosmos states 

 that in five years, terminating with 1859-60, fifty wells have been 

 sunk in the Algerine Sahara, capable of yielding 36,761 litres of 

 water per minute. 30,000 palms and 1,000 fruit trees have been 

 planted. Numerous oases have been recovered from ruin, and two 

 fresh villages established. The expense has not yet reached 298,000 

 francs, and has been covered by a slight additional tax, and by vol- 

 untary contributions from the Arabs. The water is slightly saline, 

 and a little bitter, from the presence of Epsom salts, but is not found 

 to be unwholesome. 



THE FROZEN WELL OF BRANDON, VERMONT. 



In 1859, the Boston Society of Natural History appointed a com- 

 mittee to investigate the phenomena of the so-called frozen well of 

 Brandon, Vt., described in the Annual of Scientific Discovery for 

 1860. During the past year, this committee, consisting of John H. 

 Blake, Esq., Dr. C. T. Jackson, and Prof. W. B. Rogers, have made 

 a report, the substance of which is as follows : 



The frozen well of Brandon is situated about half a mile west of 

 Brandon Hotel, on the estate of Mr. Abraham Twombley. It was 

 in the month of November, 1858, and stoned up with boulders of 

 limestone rock soon after. In excavating this well, the first strata 

 were found to be sandy loam, then came coarse gravel, and a bed of 

 rounded boulders, of sizes varying from a walnut to a foot or more in 

 diameter, the spaces between the boulders being filled with fine, 

 clayey sand. Twenty feet from the surface the boulder bed and soil 

 were found to be frozen, and lumps of frozen earth, with pieces of 

 ice, were raised, some of the lumps of ice being the size of a hen's 

 egg. Frozen masses of the earth and lumps of the ice were taken 

 away and exhibited in the village of Brandon. All the lower portion 

 of the boulder bed was frozen ; but on passing through it to the sand 

 below, liquid water was found, which flowed up into the bottom of 

 the well. The whole thickness of the frozen bed was estimated at 

 from twelve to fifteen feet. 



Before making an examination of the well the committee explored 

 the geology of the immediate environs. The gravel bed was found to 

 outcrop 250 feet north-west of the well, in a road-side cut. The 

 rocky basis on which the drift material in which the well is sunk re- 

 poses on limestone. A section of the road-side cliff showed the so- 

 called gravel bed, made up of erratic boulders, to be six feet in thick- 

 ness ; over this is a bed of gravel proper, one foot thick ; then a 

 layer of sand two feet thick, over which is a layer of ordinary sandy 

 soil, mixed with mould. From the top of the strata it is evident that 



