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improvement of grass-lands only, until its action 

 upon grain crops is fully established by experiments. 

 Dr. Pinkers, of Insterburg, -has given us some 

 valuable and carefully prepared figures with 

 regard to this manure. He ascertained its effect 

 upon clover, and established the fact that it will 

 raise the outturn of clover hay by one-half. 



The best mode of applying it, is to dust it over 

 the young plants at the rate of about 5 to 10 cwts. 

 per acre. Its effect is chiefly confined to the 

 increased production of leaves and stems, and 

 woody fibre in general ; its application would 

 therefore benefit cereals by increasing the food- 

 absorbing surfaces, and consequently increase to 

 some extent the assimilation of nourishment and 

 the outturn in seed. 



Its use in Europe has of late been increasing 

 greatly, and the results appear very satisfac- 

 tory. In a London letter to the Times of India, 

 special attention has been drawn to this manure, 

 which is highly spoken of. I extract the following 

 as most interesting : 



" The notice in your Overland Summary of the 17th 

 ultimo, of the Aden pumice-beds, has attracted consider- 

 able attention here. If the strata contain gypsum in large 

 quantities, the pumice is good for other purposes than 

 those of making hydraulic mortar, though for this purpose 

 alone the deposits must be very valuable. We often hear 

 and read of the great want of manure in India. Now, 

 here I am writing from Kent, the garden of England 



