44 REPORT—1846. 
appear that the increase of these fairy-rings is due to the large quantity of phosphated 
alkali, magnesia, &c. secreted by these fungi; and whilst they are extending them- 
selves in search of the additional food which they require, they leave, on decaying, a 
most abundant crop of nutriment for the grass. : 
On certain Principles which obtain in the application of Manures. 
By Witt1aM CHARLES SPOONER. 
This was a paper by a practical agriculturist, who has paid attention to the re- 
commendations of chemists as to the application of manures. It was pointed out 
that many of the recommendations of chemists were nearly valueless to the practical 
farmer on account of the expense involved in their employment. The direct appli- 
cation of sulphuric acid and silicate of potash were adduced as examples, the expense 
in both cases rendering their use impracticable, however valuable these ingredients 
may otherwise prove. Many other examples were given enforcing on chemists the 
necessity of connecting with their experimental inquiries the practicability of their 
agricultural applications, both with reference to economical use and the ease with 
which they may be employed. 
On the application of the Principles of a Natural System of ‘Organic Che- 
mistry to the Explanation of the Phenomena occurring in the diseased 
Potato Tuber. By G. Kempe, M.D. 
At the meeting of the Association last year at Cambridge, Dr. Kemp introduced 
to the notice of the Society an outline of the results of two years’ investigation into 
the nature of the changes effected by vital and physical agents on organized bodies, 
his principal aim being to suggest an arrangement founded upon natural affinities, 
and capable of interpreting the results of organic analysis, consistently with the phe- 
nomena which natural or artificial agents have effected. 
At an early period of the ravages committed last year by what is called the potato 
disease, Dr. Kemp was induced, by the application of elementary analysis, to attempt 
the removal of some of the difficulties in which the explanation of the subject was 
involved. The results of those analyses are recorded in the abstracts of the Cam- 
bridge Philosophical Society. By the application of the principles of the natural 
system of organic chemistry which he has suggested, the author arrived at the con- 
clusion, ‘‘ that the true nature of the affection is an abnormal tendency to premature 
germination,” and that the changes which the diseased tuber undergoes are identical 
with those which had three years previously been discovered by Erdmann, Marchand 
and Scharling to take place during the normal germination of seeds and tubers. 
Some remarks followed which all bore on the importance of autumn planting. 
Numerous striking instances were adduced in which healthy potatoes had been grown 
from diseased tubers planted in the autumn. 
Some Inquiries into the Extent, Causes and Remedies of Fungi destructive in 
Agriculture. By J. PRIDEAUX. 
lst. Extent.—DeCandolle’s theory of injurious excretions having been opposed 
by many arguments and experiments, particularly those recently published by Dr. 
Daubeny ; that of Liebig, of specific exhaustion of the soil by plants of one species, 
leaving it fit for another which required different ingredients, had been generally 
substituted. Some however had taken a middle course, and supposed plants to breed 
animalcules ; which they left in the soil, and which would feed upon other plants of 
the same species, but not upon those of different ones. The writer also, unsatisfied 
with the theory of specific exhaustion of inorganic ingredients, from the occasional 
unaccountable efficacy of ashes and soot, and the inconsistent effects of inorganic 
manures ; had investigated the organic residues on the soil,—after wheat, barley, tur- 
nips and potatoes; compared them with the premature decay of wheat (where too 
often cultivated) in patches, expanding from centres, like fairy-rings; and with the 
notoriety of fungus in the potato disease; and had thence been led to inquire how 
far such fungous parasites might be the general representatives of DeCandolle’s sup- 
ae 
