wo. | 
afthenic virtue of chemical agents, that 
is to fay, their ability or impotence to 
produce irritation. Alkalies appear to 
be to nerves, what acids are to mufcular 
affemblages. The muriatic acid auvg- 
ments the irritability of the mufcle, 
while it extinguifhes that of the nerves, 
which is not obferved again, even after 
the acid has been faturated with alkali. 
By repeatedly infufing the nerve with 
alkaline folution, an entire atony will be, 
at length, produced, through excefs of 
frritation ; if, however, a few drops of 
muriatic acid be let fall onthe part, the 
irritability will be reftored. 
A frog’s leg, irritated even toa degree 
of entire relaxation, by..a hot folution 
of oxide of arfenic, has been obferyed to 
fhow frefh conyulfions. after having been 
 fteeped for about two minutes in a folu- 
tion of pearl-afhes. 
The fthenic virtue of the muriatic 
oxigenate acid is no lefs remarkable. 
_ Frogs’ legs, which are naturally flabby, 
when farther relaxed by a Galvanifn of 
feven hours’ continuance, fo as to exhibit 
no fign of motion, when filyer was the 
conductor between the zinc and the 
nerye, have experienced again violent 
contractions, after the nerve has been 
moiftened with muriatic oxigenate acid. 
The author, in illuftration of this point, 
quotes an experiment published by him- 
felf, in the year 1793, in his Hlora Fri- 
burgenfis, the purport ef which is, that 
ordinary muriatic acid retards the ger- 
mination of plants, while muriatic oxi- 
senate acid made a plant germinate in 
feven hours’ time, to a degree which 
would have required its ftanding thirty- 
eight hours in water, to raife it to the 
fame height of vegetation ; this circum- 
ftance, according to M. Humboldt, de- 
notes a certain connection to fubfift be- 
tween vegetable and animal organization. 
From the foregoing {pecimen of faéts 
and obfervations, relative to this import- 
ant art, the public will, no doubt, ex- 
pect impatiently the larger work in 
which the experiments of M. Humboldt 
will be collected, arranged, and deve- 
loped with greater accuracy and copi- 
oufnefs. 
London, May 2, 1797. 
r 
To the Editor of the Monthly Magazine. 
SURG ic. 
your intelligent correfpondent Cr- 
vis, has afforded me much amufe- 
\ ment, by his ingenious {peculations on 
private copper comage: but as many of 
your rgacders probably refide in parts of 

Galvanifm....Private Copper Coinage. 
351 
the country where this kind of money 
has not come into circulation, the follow. 
ing letter to a friend, written on the 
date it bears, may poflibly be accept- 
able, as it may contribute to render your 
readers in general better acquainted with 
the origin and nature of this {pecies of 
currency ; and thus prepare them for en- 
tering more fully into your correfpond« 
ent’s remarks. 
Iam, fir, hisand your obedient fervant, 

Vi & 
Tole Seta |B. 
Wewcofile, Aug. 12, 1793+ 
DEAR SIR, 
THE pretty piece of mint-work you 
fhowed me at our laf&{ meeting, repre- 
fenting the inclined plane, and the iron 
bridge over the Severn, by the Colebrook 
Dale Company (at whofe works this 
coin paffes current for a halfpenny) put 
me upon examining, as foon as I return- 
ed home, whether, in’ the courfe ofa 
late journey into Lancafhire, I had not 
received in change a. number cf thefe 
metallic promiffory notes ; of which, the 
Anglefea Copper Company fet the firft 
example, and-which have fince been in- 
troduced into fo many of our principal 
manufacturing diftricis, as a fubftitute 
for that wretched mimickry of the legal 
current coin, which had, of late years, 
overfpread the country, till it was be- 
come an intolerable nuifance to the fair 
trader of every defcription. As I find 
that I have picked up in this way acon- 
fiderable variety of them, which curio- 
fity has led me to preferve, I conceived 
that the infpection of them might afford 
a few minutes’ entertainment to thofe of 
your friends, into whole way fuch things 
may not have happened to fall: fince 
the inhabitants of this part of rhe coun- 
try were, I believe, quite fingular, in 
relieving themfelves fromthe necediity 
of employing any fuch expedients ; by 
having the fpirit tounite, with one con- 
fent, to the total extirpation of the adul- 
terated copper money; and in the re- 
duétion of that fpecies of currency with- 
in its legal and proper bounds, of ferving 
only as change for the loweft denomina- 
tion of the current filver coin.—They 
are, however, in other refpects, by no 
means unworthy the notice of the curi- 
ous ; as they muft be allowed to be very 
neat fpecimens of mint-work ; and’ as 
they furnith a curious inflance, how far 
government are difpofed to comnive at 
violations of law, whea they fave them 
the trouble of remedying an inconvent- 
FO WARE ; ance. 
