131: MANURES. 



It should be particularly borne in mind that, when 

 first taken from the swamp, it is often sour^ or cold ; 

 but that if exposed for a long time to the air, or if 

 well treated with lime, unleached ashes, the lime 

 and salt mixture, or any otlier alkali, its acids will 

 be neutralized (or overcome), and it becomes a good 

 application to any soil, except peat or other soils 

 already containing large quantities of organic mat- 

 ter. 



SPENT TAN-B.VRK. 



Spent tan-harJc, if previously decomposed by the 

 use of alkalies, answei*s all the purposes of prepared 

 muck, but is more diflficult of decomposition. 



The bark of trees contains a larger proportion of 

 earthy matter than the wood, and much of this, 

 on the decomposition of the bark, becomes available 

 as manure. The chemical effect on the bark, of 

 usino- it in the tannincr of leather, is such as to ren- 

 der it difficult to be rotted by the ordinary means ; 

 but by the use of alkalies it may be reduced to the 

 finest condition, and becomes a most excellent ma- 

 nure. Unless tan-bark be composted with lime, or 

 some other alkali, it maj' produce injurious effects 

 from the tannic acid which it still contains. Alka- 

 line substances M-ill neutralize this acid, and prevent 

 it from being injurious. 



One great benefit resulting from the use of spent 

 tan-bark, is due to its power of absorbing moisture 

 from the atmosphere. For this reason it is very val- 



