JViscellanies. 179 
ped, and if the atmospheric air be removed from it by the well known 
method, clear visible sparks may by day light be discovered disengag- 
ing themselves from the neck, just a few moments before the freez- 
ing takes place. ‘This phenomenon appears to be a steady and a 
sure guide for indicating, whether the freezing will soon take place 
or not at all.— Translated by Dr. Lewis Feuchtwanger, from the 
Central Blatt, July, 1833. 
AGRICULTURE, DOMESTIC ECONOMY, &e. 
Translated by Prof. J. Griscom. 
1. Observations by M. Boutigny D’ Evreux, on a new theory 
of the action of manures and of their employment; by M. de la 
Giraudieu.—M. de la Giraudieu, President of the Agricultural So- 
ciety of Loir-et-Cher, concludes from his own experiments that 
the weight of the produce of land is in proportion to the weight of 
manure with which it is enriched ; and that soil, of whatever nature 
it may be, has only a mechanical agency in vegetation, and is no 
otherwise important than as a support to plants. 
The first of these conclusions deserves notice, and agriculturists 
are indebted to M. de la G., for a communication of the curious and 
important fact, of a direct ratio between the manure and. the pro- 
duce. ‘To assert, in fact, that the amount of produce is in propor- 
tion to the manure, is as much as to say, increase the number of 
your cattle that you may increase your manure, and thus double or 
treble your harvest. Better advice cannot be given, and no one 
has a better right to give it, than the President of the Agricultural 
Society of Loir-et-Cher. Since it is suggested by the result of ac- 
tual experiment. Experientia index. 
Bat I am far from uniting in opinion with M. de la G., with re- 
spect to the action of soils, independently of manure, and of the 
manner in which manure operates. 
This author pretends, that calcareous, argillaceous, ferruginous or 
sandy soils act only as supports, like sponge, pounded glass, &c., 
this, I think, is erroneous and that no one can call in question the 
action exerted by the soil on vegetation. Who does not know that 
a soil composed in equal parts of siliceous sand, clay and carbonate 
of lime possesses great fertility, when well watered, although it may 
be completely destitute of vegetable remains? But how’can this phe- 
nomenon be explained ? 
Admitting that the clay retains water, a portion of which however 
evaporates, an electric current is established ;—admitting also, which 
