340 



NEW ENGLAND FARMER, 



APRIL S7, 1S4I 



Trom Dr. Dana's Muck Manual. 



IRllfGATtONT. 



Before it can be uiiJerstooJ how irriffallon acts, 

 Set it be considered liow pure wnlcr nets ; it is imt 

 Baid rain waler, for that acts in a double way, both 

 by iti purity and impurity. The moro impure, the 

 better niamiro is water. The purer water is, the 

 Jess is it fit for irrigation. 



Pure waler acts only by its air. All water ex- 

 posed to air, alEorbs dilferent proportions of its 

 oxygen and nitrogen. This is a very slow process. 

 It is found that most natural waters give out, by 

 boiling, from every hundred cubic inches of water, 

 ;J 1-2 cubic inches of air. This air contains 8 or !) 

 per cent. mor» oxygen than an equal bulk of com- 

 mon air. Wati;r is generally tilled or saturated 

 with air ; it will tako up no more by a month's ex- 

 posure. If this waler is boiled, and again c.\po3cd 

 to air, it will absorb, in 24 hours, as follows : Let 

 there be taken any number of measures of air, 

 which are composed of 20 of oxygen and 80 of ni- 

 trogen. If 100 measures are absorbed by water, it 

 is in this proportion — 4C.43 of nitrogen, 5;i.57 of 

 ■oxygen : so that oxygen is three times more ab- 

 sorbable than nitrogen. 



If, now, there is expelled by boiling, the air 

 from pond or river water, it is found to contain 

 45.2y of nitrogen, J8.(>3 of o.\ygen: so that two 

 thirds of the oxygon have disappeared ; this is the 

 only fact which concerns the farmer. The oxy- 

 gen has been absorbed by natural waters, and two 

 thirds retained. What has become of it .^ It has 

 gone — it is not said all of it, but in irrigation a 

 large portion — to convert insoluble into soluble 

 geine. Irrigation is chiefly employed on grass 

 lands. The green award hero may not be broken 

 up. What if it was.' What if, by plowing, it 

 was exposed to the action of the nir? Remember 

 the properties of geinc. Air converts the insoluble 

 to souble, by forming carbonic acid — that is, the 

 • ir combines with the carbon of the geine, and 

 forms that gas. Give the geine this oxygen, con- 

 densed in water : wet it with this concentrated oxy . 

 gen, crowd it into geine, ss would be done by over- 

 flowing a meadow with water. It penetrates every 

 crack and cranny, and every 'mole's-eye hole; it 

 expels the carbonic acid im;-i86nc(l under the sod. 

 It is doing the saiiio work upon the untouched 

 green sward, which would bo effected by plowing 

 and tillage. The long and the short of the whole 

 action of irtigation with pure limpid water is, that 

 its absorbed oxygen, converts insoluble to soluble 

 geinc. Is this explanation which science offers, 

 confirmed by practice ? The appeal is made to 

 all who have attended either to the theory or prac- 

 tice of irrigation, to bear witness lo its truth. Is 

 it not admitted that running waters are alone fit for 

 this purpose .' That after remaining a few days, 

 Ihey are abated and a new flood must cover the 

 land .^ Is not this necessity of renewing at short 

 periods, the covering of water, which shows no de- 

 posit, a proof that it has given up some invisible 

 agent to fertilize the earth ? Tim invisible agent 

 is oxygen. Is it not evident from the extreme 

 slowness with which nir is obsorbed by water, that, 

 if it were not for the running water, which every 

 few days replaces that which has acted, that the 

 practice of irrigation with pure water could be never 

 successful ? 



This 18 tho principle, a principle which, having 

 been wholly overlooked, has led lo a waste of 



time and money, and has given to irrigation, in 

 many minds, the odor, if not of a bad, at least, of a 

 useless practice. Where, guided by this light of 

 science, grass lands can be irrigated, let it be 

 done. If the experience of the most enlightened 

 agriculturists in Europe is not all deception, by 

 simple irrigation with running water, tho farmer 

 may cut two tons of hay, where he toils and sweats 

 to rake off one. 



But by far the most fertile source of increasing 

 crops by irrigation, is found in the impurity of wa- 

 ter ; the salts and suspended matter, the slime and 

 genial mud of freshets. Perhaps the elTects due 

 to this cause, cannot be better illustrated, than by 

 a statement of those substances and their amount, 

 which fill the waters of the Merrimack — a flood of 

 blessings! which rolls by those engaged in the 

 din and hot haste of manufacture, as unheeded as 

 was the carthqiir.ke, which thundered and trembled, 

 and rolled away under the feet of the fierce sol- 

 diery, in an oncicnt battle. In the year 1838, 

 during twentythree days of freshets, from May till 

 November, no less than 71,874,003 pounds of geine 

 and salts rolled by the city of Lowell, borne sea- 

 ward. During the five days of the great freshet, 

 from January 28th to February let, 183!t, no less 

 than 35,970,807 pounds of the same matter rolled 

 by, at from the rate of 112, 128 pounds, to 20,40,5,- 

 3'J7 pounds per day ; each cubic foot of water bear- 

 ing onwards from 1 1-2 to 30 1-2 grains. This is 

 only the suspended matter. That which is chemi- 

 cally dissolved by the waters, the fine filmy deposit, 

 which occurs in a few days after the coarser and 

 grosser matters subside, and tho matter ordinarily 

 suspended in the water of the river added to the 

 above, for the year 1838, give a grand total of 

 8.39,181 tons of salts and geine, which wero rolled 

 down in the water of the Merrimack river. 



What is this matter.' Is it of any agricultural 

 value .' The answer to the first question will an- 

 swer both. The dissolved salts are sulphate and 

 geate of liine, and the fine deposit occurring after 

 the water has settled, is composed of one half of 

 geine, and the remainder of salts of lime and sili- 

 cates. Tho great agricultural value is found in 

 the clayey deposit which occurs in tho first few 

 days. Tho coarser part, that which collects about 

 the foot of rocks, and falls, and eddies, is composed 

 as follows : 



Geine, 3.92 



Silex, 72.70 



Oxide of iron, 9.)5 



Alumina, 8.30 



Lime, o..'51 



Magnesia, 0.10 



But considering tho elements as we have usually 

 treated tliem, as silicates, salts and geine, tho com- 

 position of the several deposits is shown in the fol- 

 lowing table : 



delne. Sulph. Phot, of Sili- 



Soluble, /nsolu. of lime. lime. eaten. 



The coarse de- 

 posit above. 



Freshet, 18.39, 



Freshet, July 

 7-18, '39, 



If the doctrine of the action of silicates, salts 

 and geinc, upon each other when aided by growing 

 plants, i^ considered, it cannot fail to bo perceived 

 that tho fertility of soils, periodically overflowed by 

 turbid waters, is owing to the elements, salts and 

 geine which it contains, and to the exquisitely 



finely divided slate of the silicates which form til* 

 bulk of the deposit. The carbonic acid of the 

 acts on cich atom of silicate, while owing to tl i" 

 geine having been, as it were, irrii^ated, the ox 

 gen of tho air and wotcr, must put that into 

 stale lo evolve carbonic acid. Hence, the silicat. i 

 are at once decomposed, and their alkali liberate 1 

 How beautiful! It seems like a special intcrpoti 

 lion of that Beneficent Power, whose blessing 1 

 while they fill us with wondering admiration, 1 

 the infinite skill which directs every change in tt 

 iiiatcrial universe, should teach iis also, that thw li 

 changes are held up to us, not only to admire, bi 

 in some hiimblo degree lo iiiiilnte. Whenevi 

 man, " tho fuithful servant and interpreter'of in i. 

 lure," has thus learned the lessons propounded I ^ 

 an Infinite mind, he finds when he humbly imitati V 

 nature's laws, she is a kind and indulgent paran ■, 

 She opens her hand liberally, and gives fertility b ,! 

 irrigation, and rivers and streams like holy wati '. 

 sprinkled by a reverend father, fructify all they b( 

 dew. With hearts thus attuned by the obsem 

 lion ff the laws of nature, they respond to the n« 

 tic vibrations, caused by the descent of genial aiiil 

 fertilizing showers. 



Rain is only natural irrigation: tho water ^t 

 found, like that of rivers, rich in oxygen and cn." 

 ganic matter. The fertilizing power of rain, is n 

 fcrrcd to the same causes which lead to irri-'atioi 

 to the salts and geinc, which rain water contaiB 

 Several chemists have proved the existence of iii j 

 line matters and organic substances in the air. TbI ^ 

 falling rain carries down with it sails of ammonil 

 of lime, and a flocky organic matter. These «l 

 may be supposed floating in the nir. The dr 

 soils give to the winds nn impalpable dust, its sili 

 cates and geine. When hailstones, which 

 been formsd in the regions of perpetual frost, ex 

 bit almost tho same substances which arecontaL 

 in rain water, the height at which these matti 

 float, would almost compel the supposition ibn 

 they exist in a gaseous state. From the examioM ,1 

 tiun of hailstones, by Girardin, a I'rwnch chcmir' 

 it appears that no sensible trace of ammonia 

 detected during the evaporation of their waler, bu 

 there was found a notable quantity of lime and sul 

 phuric acid ; and above all, a large proportion ofi 

 organic substance containing nitrogen. Melte^ 

 hailstones have the appearance of water, contain 

 ing a drop or two of milk; by standing, the watt 

 grows clear, and the flocky matter which settle* 

 burns with the smell of animal matter, and evolr 

 ammonia. 



It is a question whether even at the Giessen la- 

 boratory, this was not the source of the ammooil 

 there discovered in rain water. It is taken fa 

 granted, that the ammonia in rain water existed I 

 a volatile carbonate, because it was found to pal 

 over in distillation. So did a volatile product 

 which aU-dys discolored the crystals of sal amo^ 

 niac, procured by adding muriatic acid to tho die- 

 tilled water. This coloring matter, was noticed • 

 century ago by Margraf. Later chemists ban 

 also detected ammoniacal salts in rain water, bsl 

 no volatile carbonate of tliat base. It is well knovi 

 that muriate of soda arises in evaporation, so doSI - 

 chroinato of potash, and several other salts. Ifi|| 1 

 distilling rain water, tho ammonia did not pM< 1, 

 over in the volatile organic discoloring producVil 

 may have gone over as muriate of ammonia. Mt 

 not questioned that ammoniacal salts exist in tiki 

 and snow water. The fact that it there exietf< 

 carbonate, secmi to be assumed, and is incompatf* 



fiav 



'"lis 



