i6o 



Tlic Count)-)' Gentleman s Llagazinc 



MANURE TANKS. 



LIE13IG, in his "Familiar Letters," says 

 that I lb. of urine contains the ele- 

 ments necessary to form i lb. of grain ; for 

 not only does it possess a compound rich 

 in nitrogen — viz., urea— hut also the sulphur 

 of the tissues in the form of a sulphate, all 

 the soluable salts of the blood and animal 

 fluids, common salt, the phosphates, soda 

 and potash. Well-authenticated experiments 

 are not wanting to prove the soundness of the 

 views of the great chemist. 



There are few farmers who will not admit 

 the value of the liquid manure of their stables 

 and byres ; but not one in a hundred takes 

 proper means to preserve it, or to fix the 

 ammonia even when they have gone to the 

 expense of providing a suitable tank. Urine 

 speedily undergoes putrefaction, thereby gene- 

 rating a large quantity of ammonia ; and as this 

 is a very volatile body, it flies off into the air 

 unless some means are taken to fix it. Two 

 most important practical conclusions follow, 

 therefore, from a consideration of this pro- 

 perty : — I St, That when urine is allowed to 

 flow into a fermenting dunghill, the surest 

 means are taken to waste the ammonia both 

 of the urine and the solid excrements of the 

 dunghill ; and 2d, there is loss, although to a 

 less amount, by allowing putrefaction to go 

 on in a covered tank, unless some substance 

 is put there to fix the ammonia as it is gene- 

 rated. In Flanders, where great attention is 

 paid to this subject, the fresh urine is diluted 

 with a large bulk of water, and thus a good 

 deal of the ammonia is retained, although 

 there is still a considerable loss. This method 

 of dilution, moreover, increases the expense 

 of applying it to the land, and is scarcely 

 compatible with the methods of farming fol- 

 lowed in this country. In the smaller Flem- 

 ish farms a small tank is constructed below 

 the floor of each byre, and the contents are 

 diluted and applied direct to the land. 



Mr Hemy Stephens, the best authority on 



all matters pertaining to the economy of farm 

 management, does not consider that tanks are 

 necessary on all farms. In his excellent 

 work, " The Book of Farm Buildings,"-'' he 

 says that on carse lands where much straw 

 and little green food is used, there can be no 

 liquid manure ; and on pastoral farms the 

 stock confined in winter in the steading are 

 too limited in number to afford much of that 

 material. On dairy farms, on the other hand, 

 where many cows are maintained, and much 

 green food consumed by them in byres, 

 tanks should be constructed for the advantage 

 of the pasture land ; and he recommends that 

 on all small dairy farms the Flemish practice 

 of constructing a small tank underground 

 should be followed. 



T\\Q. principles to be observed in the con- 

 struction of liquid manure tanks are thus set 

 forth by Mr Stephens : — 



" The cistern for collecting liquid manure 

 in the farmstead, though apparently simple in 

 its construction, being merely a covered pond 

 or a well, yet serious errors are frequently 

 committed in its formation. The first and 

 most important consideration for the forma- 

 tion of the cistern is the effect of hydrostatic 

 pressure ; inattention to this has caused the 

 failure of many such cisterns. Theiiquid we 

 have here to deal with, like all other fluids, 

 acts on the bottom and sides of the vessel or 

 body that contains it, with a pressure directly 

 in proportion to the depth at which the fluid 

 stands, without reference to either length or 

 breadth ; that is to say, suppose a cistern, 

 whose bottom is 12 inches square, and its 

 depth 10 feet, filled Avith water, every square 

 inch in the bottom will suffer a pressure equal 

 to the height of a column of water whose base 

 is one inch square, and 10 feet or 120 inches, 

 in height. The weight of such a column will 



* The Book of Farm Biuldings ; their Arrangement and 

 Construction. By Henry Stephens, F.R.S.E., and Robert Solt 

 Burn. W. Blackwood & Sons, Edinburgh and London. 



