226 [Senate 



modes of manuring; the quantity of foreign matter thus held in solu- 

 tion, and the enriching power it possesses, are often almost incredibly- 

 large, even though it may appear but little discolored by their presence. 

 There are, of course, various degrees of foreign and fertilizing matters 

 to be found in water, according to circumstances; from the purest 

 brook or river water, to the heavily loaded drainings of the city sewer, 

 or the farmer's manure tank. * 



In England, and in all countries so cool and moist that plants do not 

 suffer greatly from drought, the chief benefit resulting from irrigation^ 

 arises from the foreign matter contained in the water. Hence it 

 becomes a very important object to obtain such streams as contain the 

 most enriching substances. Some interesting illustrations of this fact 

 have been given to the public. In one case, a gentleman who owned 

 meadows on the bank of the stream which passes through Winchester, 

 observed the great superiority of the waters of the stream below the 

 city, after they had received the drainage of the sewers. The benefits 

 which the plants derived from the water, was strikingly shown by its 

 deteriorated quality after it had passed over the fields and imparted its 

 fertility to the plants. On one occasion, after having long enjoyed the 

 exclusive use of a stream, his neighbor, higher up, imitated his example ; 

 and the water, in consequence, was so reduced in value, that he thought 

 of disputing the right with him. 



An interesting experiment was made in Scotland, to show this 

 abstraction of dissolved substances by the plants. A stream of water 

 before its use in irrigation, was analyzed, and was found to contain per 

 gallon about 10 grains of common salt, and 4 grains of the salts of 

 lime. After passing over 50 yards of meadow, it was again analyzed, 

 and yielded only 5 grains of common salt to the gallon, and 2 grams 

 of the salts of lime. ' 



A long continued flow of the water will thus impart to the plants a 

 large and most important quantity of mineral as well as organic manures. 

 It is not necessary that streams should always appear to the eye turbid 

 or impure, in order to be well adapted to this kind of manuring ; in- 

 deed, a turbid stream, rendered so by the suspension of clay merely, 

 may be less valuable than a limpid stream, which holds gypsum and 

 various other salts in solution. Several analyses have shown that all 

 hard waters contain considerable portions of gypsum or sulphate of 

 lime ; and that not unfrequently every two thousand parts of the water 



