418 Abstract Report of Arjricultural Discussions. 



There is only one other point to ^^•hich I may refer, it is the in- 

 creasing favour with which these salts are regarded by agriculturists 

 in Germany. A few days ago I received a letter informing me that 

 orders had been procui'ed by Dr. Frank, who was the first to establish 

 potash works, for upwards of 3,000 tons of crude potash-salts. Thus, 

 at any rate, should there ever be a real deficiency of potash, we have in 

 these extensive mines of Germany a supply which will make up the 

 deficiency, and Ave need not be afiaid therefore that the land of England 

 may become exhausted of its jiotash. Phosphoric acid has been sup- 

 l)lied, and can be supplied in still larger quantity if there is really the 

 demand ; and I have no doubt that potash, should it be required, can 

 be supplied from the mineral deposits of Germany, and probably of 

 other countries where they Anil be discovered on fui-ther search. It 

 is not a little remarkable that, just as a demand increases, om- national 

 sources of supply also increase, and, for aught I know, we may have 

 here in England these very skim-salts which we now import from 

 Germany. At any rate, the new red sandstone formation — the same 

 formation in which the salt-mines of Germany occm* — is the spot in 

 which to look for these potash-salts. 



Mr. P. H. FitKiiE wished to be informed whether in the iorm of 

 chloride of potassium tlie salt would be objectionable. 



Dr. VoELCKEH did not think it would be objectionable ; but sulphate 

 of potash v.ould be better, because it dissolved more gradually, and 

 supplied the 2>hints with sulphuric acid, Avhich was a great advantage. 



Professor Wilson observed that the meeting must be of one mind 

 in reference to the subject introduced by Di*. Voelcker — that it is one 

 of vast importance to agriculturists. He would not attempt to speak 

 dogmatically as to the principles that ought to guide them in manuring, 

 they must all admit that the true princijile of manuring was to supply 

 to the soil those substances which they knew to be necessary for the 

 gi'owth of their crojis. And if they trusted to analyses of ashes of 

 plants, they must be struck with tlie very large proi)ortion in which 

 potash existed in all cultivated plants. Potash Avas essentially the 

 alkali of vegetable life, as soda was the alkali of animal life. For 

 many years past, hoAAever, it aiq)eared to him that tliey had been 

 going u2)ou rather a Avrong system in manm-iug ; they had been giving 

 very large doses of one necessary ingredient, but either totally omit- 

 ting or else applying very small doses of another ingi'edient that Avas 

 equally necessary, as he believed potash to be. Consequently their 

 results had fallen short of those Avhich might have been obtained by 

 an outlay of the same amount of money more judiciously applied. 

 The produce of the soil AAas determined rather by that constituent 

 which AAas in defect than by that of Avhich the supply Avas largest. 

 If a soil is analysed there is as gi-eat difficulty in detecting the potash, 

 as in detecting the phosphoric acid, for they exist in about the same 

 proportion in soils ; and yet they had been going on the system of 

 adding considerable doses of phosphoric acid to the soil, and small 

 doses of jiotash. There had been a difficulty in obtaining sufficient 

 potash, and giving it in such j)roportions as farm-crops required. A 

 search after potash in different countries had been prosecuted for many 



