h.5. 



Irrigation. 



145 



aluable paper. We have long believed, and bave 

 ideavoured to inculcate tlie opinion, that farmers in 

 lis vicinity— perhaps we might include the whole 

 luntry— do not sufficiently appreciate the value of 

 rigation, and consequently do not avail themselves 

 i they might, of the power they have in many situa- 

 ons,to throw the running streams over their grounds, 

 is by frequently calling attention to subjects of this 

 laracter, that we may hope gradually to accomplish 

 ime good. — Ed. 



A SUPPLY of water to plants, is essential 

 n two accounts. First, it is necessary that 

 11 plants in a growing- state have at hand a 

 jpply of the water which enters so largely 

 ito their composition. Secondly, that there 

 e enough to dissolve freely all substances 

 'hich ascend tlirough the stem from the 

 jots; for without solution, no fertilizing 

 jbstances can enter the plant. 



The large quantities of water needed 

 uring vegetable growth, are evident from 

 le abundance which exists in nearly all 

 ving plants. Some plants contain more 

 lan three-quarters of their weight, and 

 lost others more than one-half In addition 

 ) this, the enormous quantities thrown off 

 1 hot dry weather by perspiration, amount- 

 ig sometimes to the entire weight of the 

 lant in a day or two, or to several tons 

 aily from an acre, render an abundant sup- 

 ly still more important. Hence the reason 

 ley droop and wither so soon, when the 

 sual supply is withheld. Water also, of 

 .self, forms an essential portion of tiie food 

 f plants, by furnishing nearly all the hy- 

 rogen they consume. 



But a most important office performed by 

 /ater, is its solvent power. During its fall 

 1 rain, in washing and purifying the atmos- 

 here as it descends, it brings down matter 

 /hich had previously risen in the form of 

 apor; and afterwards as it flows along the 

 urface or through the soil, it dissolves many 

 olid substances, and becomes charged with 

 arious matters of organic origin, which 

 lossess more or less highly fertilizing pow- 

 rs, and which are thus conveyed in a fluid 

 arm to the roots of plants. Water thus 

 lecomes one of the best and most efficient 

 nodes of manuring; the quantity of foreign 

 natter thus held in solution, and the enrich- 

 Qg power it possesses, are often almost in- 

 iredibly large, even though it may appear 

 tut little discoloured by their presence, 

 rhere are, of course, various degrees of 

 breign and fertilizing matters to be found 

 n water, according to circumstances; from 

 he purest brook or river water, to the hea- 

 vily loaded drainings of the city sewer, or 

 he farmer's manure tank. 



In England, and in all countries so cool 

 ind moist that plants do not suffer greatly 



from drought, the chief benefit resulting 

 from irrigation, arises from the foreign mat- 

 ter contained in the water. Ilencc it be- 

 comes 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 mea- 

 dows on the bank of the stream which 

 passes through Winchester, observed the 

 great superiority of the waters of the stream 

 below tlie city, after they had received the 

 drainage of the sewers. The benefits which 

 the plants derived from the water, was strik- 

 ingly 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 neighbour, higher up, imi- 

 tated his example; and the water, in conse- 

 quence, 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 dis- 

 solved substances by the plants. A stream 

 of water before its use in irrigation, was 

 analyzed, and was found to contain per gal- 

 lon about ten grains of common salt, and 

 four grains of the salts of lime. After 

 passing over fifty yards of meadow, it was 

 again analyzed, and yielded only five grains 

 of common salt to the gallon, and two grains 

 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 or- 

 ganic manures. It is not necessary that 

 streams should always appear to the eye tur- 

 bid or impure, in order to be well adapted 

 to this kind of manuring ; indeed, a turbid 

 stream, rendered so by the suspension of 

 clay merely, may be less valuable than a 

 limpid stream, which holds gypsum and va- 

 rious other salts in solution. Several ana- 

 lyses have shown that all hard waters con- 

 tain considerable portions of gypsum or sul- 

 phate of lime; and that not unfrequently 

 every two thousand parts of the water of 

 our rivers and brooks, contain one part of 

 gypsum. If, therefore, every square yard 

 of common meadow soil absorbs only eight 

 gallons of water, more than a hundred 

 weight and a half of gypsum per acre, is 

 thus diffused through the soil. 



It would be hardly possible to convince 

 the community of the enormous amount of 

 wealth lost to the country yearly, by a ne- 

 glect to secure the liquid manure with 

 which it abounds. The quantities which 

 are every year swept from our fields and 

 farm-yards, and carried through our lands, 

 unapplied, in running streams, into our riv- 



