482 
Notices. 
rium that contains it ; but I am not anxious hastily to publish my 
collections, for fear that many if not most of the facts and pro- 
cesses may be forestalled by these proposed publications. I hope 
to make that article when I come to it, a good one ; which I can- 
not, without looking at tliQ latest sources of information. T. C. 
Potatoes. I consider the paper of Mr. Curwen on this subject, 
so fully corroborated, and in a manner so very different, by the 
experiments of Professor Davy, as very important. If an acre in 
potatoes yields but tnmce the weight of produce, as an acre in 
wheat, it affords an equal weight of nutriment. But an acre in 
potatoes equally well managed, will afford near twenty times tl^e 
weight : nor is there great difference in the expence of cultiva- 
tion ; for potatoe ground highly manured, is the very best prepa- 
ration for a wheat crop. In my neighbourhood in Lancashire and 
Cheshire, potatoes (when an early and a late crop were raised for 
the Manchester market) would justify twenty pound sterling, a 
Lancashire acre (about ^ more than a statute acre) in manure. 
The inferences in respect of national as well as individual saving 
from the facts stated, are of the very first moment. T. C. 
Lightning. The following cautions respecting the danger 
that may occa.sionally arise from lightning, are sufficiently obvious, 
but they deserve to be frequently brought into notice. T. C. 
In storms of this kind we are frequently, from inadvertence, 
exposed to imminent danger, when a timely, and in general a very 
practicable, mere change of station would secure us against it. 
It has been long known that the cause of thunder, is the same 
with that which produces the ordinary phenomena of electricity ; 
thunder being no other than a grand species of electricity, or, ra- 
ther, that electricity in the hands of man is a feeble imitation of 
thunder from the hand of the Almighty. A thunder-cloud may 
be considered as a large conductor, actually insulated and sur- 
charged with electric matter ; which, should it meet with another 
cloud not electrified, or less so than itself, wdll discharge part of 
its subtile fluid into the latter, by flashes of lightning and formi- 
dable reports of thunder ; until an equilibrium of quantity be re- 
atored. 
Whether this principle, the electric fluid, actually emanates 
from the sun, and commixes with our atmosphere, as some phi- 
losophers conceive ; or whether it is a principle inherent in th 
and its appeIl4ageS;/^fr is a question not necessary to b 
