254 Mr. A. B. Northcote on the Water of 



ages, present a tolerable uniformity of composition ; and he con- 

 ceives that the detritus which these rivers are carrying to the 

 sea will pass, in lapse of time, into rocks of like character when 

 the necessary indurating and cementing processes shall have 

 been passed through*. Such, therefore, may be the formation 

 now in progress at the mouth of the river Severn. 



My attention was first drawn to the water of the Severn in 

 the year 1857, about which time new waterworks for the supply 

 of Worcester from this source came into operation ; my inten- 

 tion then was to analyze it at intervals of three months during 

 the year 1857-58 ; but circumstances obliged me to content my- 

 self with making incomplete analyses. The results then obtained 

 are, however, of interest, as they afford various points of compa- 

 rison with the water of the past year, which I have had more 

 favourable opportunities of examining. 



On the 12th of April, 1866, I collected a specimen from the 

 middle of the river just above the place at which the waterworks 

 draw their supply ; this point is about a mile above Worcester. 

 After a period of dry weather, rain had fallen on the preceding 

 day, and a rise of 4 inches in the level of the river showed that 

 rain had also fallen up the country. The river was muddy, 

 and the portion collected deposited the sediment of which the 

 composition has been given ; the water remained opalescent, in 

 which state it was analyzed, for ordinary filtration or rest for a 

 moderate length of time had scarcely any effect in clearing it. 

 When seen through a depth of 2 feet in a vessel of 3 inches dia- 

 meter standing upon a white surface, it was of a slight yellowish- 

 brown colour; and it was feebly alkaline to test-paper. 



On the 23rd of July, 1866, a specimen was sent me from the 

 same part of the river. There had been continued dry weather 

 almost throughout the course of the Severn for more than a 

 fortnight, and at no time during the previous month had the 

 river risen 2 inches. After rest, the water deposited a very tri- 

 fling sediment, and remained slightly opalescent; when seen 

 through a depth of 2 feet, it was of a very decided yellowish- 

 brown colour ; it was alkaline to test-paper. 



On the 30th of October, 1866, a specimen was collected for me 

 from the middle of the river at Bailey's Ferry, which is about 

 500 yards higher up the river than the waterworks above 

 mentioned. Early in the month of October the river had been 

 exceedingly turbid, and had at one time risen 7 feet above its ave- 

 rage height; but it had fallen and cleared gradually up to the 

 time at which the specimen was taken. The water deposited a 

 sediment in quantity sufficient for determination, and remained 



* Bischof, Chem. and Pbys. Geology (Cay. Soc), vol. i. pp. 122-124 & 

 133 ; and vol. iii. p. 67. 



