COMPOSITION OF LONG-BURIED BONES. 449 



skilful man will prefer to use boiled bones because they are fitted to 

 produce more immediate effect wiiere — as in the pushing forward of 

 the young turnip plant — such an effect is particularly required. 



4°. When bones are buried in a more or less entire state, as they oc- 

 casionally are about the roots of vines and fruit trees, they gradually 

 decay, and sensibly promote the growth of the trees to which they are 

 applied. Yet after the lapse of years these same bones may be dug up 

 nearly unaltered either in form or in size. The bones of a bear and of a 

 stag, after being long buried, were found by Marchand to consist of— 



Bones of the bear buried 



deep. shallow. Femur of a stag. 



Animal matter 16-2 4-2 7-3 



Phosphate of lime 56-0 62-1 54-1 



Carbonate of lime 13-1 13-3 19-3 



Sulphate of lime 7-1 12-3 12-2 



Phosphate of magnesia 0-3 0-5 2-1 



Fluoride of calcium 2-0 2-1 24 



Oxide of iron and manganese. 2-0 2-1 2-9 



Soda M 1-3 — 



Silica 2-2 2-1 — 



100 100 100 



The most striking change undergone by these bones was the large 

 loss of organic or animal matter they had suffered. The relative 

 proportions of the phosphate and carbonate of lime had been com- 

 paratively little altered. The main effect, therefore, produced by 

 bones when buried at the roots of trees, and their first effect in all 

 cases, must be owing to the animal matter they contain — the ele- 

 ments of this animal matter, as it decomposes, being absorbed by the 

 roots with which the bones are in contact. 



Such facts as this prove, I think, the incorrectness of the one-sided 

 opinion too hastily advanced by Sprengel, and after him reiterated 

 by Liebig and his followers — that the principal efficacy of bones is, 

 in all cases, to be ascribed to their earthy ingredients, and especially 

 to the phosphate of lime. 



This opinion of Sprengel rests mainly on two facts put forward by 

 himself (Lehre vom Diinger, p. 153.) Bones, he says, have failed to 

 produce in North- Western Germany the good effects for which they 

 are so noted in England, yet in the same districts, farm-yard and other 

 animal manures exhibit their usual fertilizing action. It cannot, there- 

 fore, he concludes, be the animal matter of bones to which their benefi- 

 cial influence is to be ascribed. But to this conclusion we may fairly 

 demur, when we know how often on heavy and undrained lands bone- 

 dust fails even among ourselves. Let bones be tried for the turnip 

 crop — a crop still almost unknown in Northern Germany — and upon 

 well drained soils similar to those of our best turnip lands, and I ven- 

 ture to predict, in opposition to SprengePs experience, that bones will 

 no longer fail even in Mecklenburg. 



Again, having drawn his conclusion in regard to the inutility of the 

 animal matter, Sprengel states that the marl which is applied to the 

 land in Holstein and the neighboring provinces, contains phosphato 



