464 TRANSACTIONS OF THE AMERICAN INSTITUTE. 



SPENT HOPS. 



So long as the brewers use hops in the way they now use them 

 they form, when properly treated, a good manure. The whole 

 soluble portion of the hop is resident in the farina fecundi. If 

 you will beat a bale of hops so as to separate the pollen entirely, 

 you can take the whole bale of leaves and they will not render a 

 quart of water bitter. A tin can full of the pollen of the hops 

 will have the same value as the bale, and the leaves need not be 

 present in the beer to soak up any part of it. But the inorganic 

 matter of the hop is principally resident in its leaf, and conse- 

 quently it must have high value as manure, provided you can 

 obtain it near enough not to have to cart the large bulk which it 

 claims from its configuration. There are certain peculiar proxi- 

 mate acids in the hop, after the brewer has done with it, which 

 require correction. This may be done with any alkali, and a 

 very little of it. It then forms an admirable manure. So in 

 England the malt dust is very largely used. 



LEATHER PARINGS 



require to be first treated so as to decompose the tannic acid. 

 Three bushels of caustic shell lime with one bushel of salt, so 

 mixed as to change the whole of the lime into a chloride of lime, 

 and the whole of the salt into a carbonate of soda, will make 

 four bushels with which the leather chips may be covered and 

 kept moist until their condition is changed, and the tannic acid 

 decomposed. They may then be mixed with large amounts of 

 inert matter, such as swamp muck, etc., and will make a compost 

 valuable from the inorganic matter given up by the leather, 

 which of course is present in the condition you want it. 



HAIR AND FEATHERS 



give you so much albumen and so little of other materials that I 

 never found them useful excepting for celery ; but for celery they 

 are the best manure you can get. I have found with them the 

 most astonishing results, and in many instances have noted that 

 both ends of the hairs would have hold of the celery root and be 

 looped. 



Mr. Robinson. — They are good on grass. 



Prof. Mapes. — So are leghorn bonnets, or anything that will 

 cover the surface and still permit the air and light to per- 

 meate it. 



