232 ANNUAL OP SCIENTIFIC DISCOVERY. 



greater content of every nutritive mineral ingredient, both soluble in 

 water and in acids, than exists in another soil from Frankcstein 

 which produces clover and wheat as well. What proves beyond a 

 doubt that the inability of these soils to yield clover depends upon 

 something besides their chemical constitution, is the fact that lucerne 

 and esparsette still flourish upon them admirably, and, further, clover 

 itself, if sown with one of these last-mentioned crops, succeeds very 

 well. 



A great truth in agriculture is this : each kind of agricultural 

 plant requires that its seeds be surrounded with certain conditions 

 in order that they may germinate readily and healthfully, so that 

 when the mother cotyledons are exhausted, the young plants shall 

 attack the stores of food in the soil with that vigor which is needful 

 in order to appropriate them without hindrance. 



The fact that winter wheat is more delicate and fastidious in its 

 infancy than most other crops, is perhaps the main reason why it 

 does not succeed well on many good lands, and why it cannot be 

 continuously produced from the same soil year after year. It is a 

 matter of experience that wheat requires a rather firm seed-bed : 

 beans, oats, and mangold-wurzel approach wheat in their require- 

 ments, while barley, peas, and turnips are best suited in a light tilth. 

 On the other hand, climate, weather, and tillage so influence the 

 character of the soil, that even on light lands wheat may find all the 

 conditions of its growth. The bed which is produced by inverting a 

 clover sod, and allowing it to be consolidated by time and rains, or 

 by passing a heavy roller over it, is eminently adapted to wheat, 

 even on a rather light soil. 



The fact that, in the cases given above from Stoeckhardt, clover 

 succeeded when sown with lucerne or esparsette, would indicate that 

 possibly the condition of the seed-bed was the cause of failure. 



These and other facts, which might be adduced to almost any ex- 

 tent, indicate sufiiciently that chemical analysis alone, even if we 

 admit its full nicety and accuracy, can at the best furnish us with a 

 knowledge of but a few of many conditions which must cooperate in 

 profitable agricultural production, and as a consequence its part in 

 guiding the farmer is but very subordinate. Taking into the account 

 its evident uncertainty and clumsiness when applied to estimating 

 the minute quantities which affect vegetable growth, the part it can 

 play becomes still more subordinate we hesitate not to say, insig- 

 nificant. 



As we write, a fragment from a scientific journal brings to our 

 notice a discovery which, if real, strengthens our views in an unex- 

 pected manner. It is well known that iodine is so immensely diluted 

 in sea-water the soil of marine plants that none of our tests, 

 though they are among the most delicate, serve to detect it directly, 

 and it is doubtful if it has been detected even in the highly-concen- 

 trated mother liquors which remain after separating the crystallizable 

 salts, yet the fuci find and accumulate it, and we must grant that it 

 is present there for them, in sufficient quantity. 



Again, Prince Salm Horstmar, several years since, in his admirable 

 researches on the influence of the individual mineral ingredients of 

 plants on the development of oats and barley, found that he could 



