The Sun.
London, England, 1847-03-19 00:00:00

Untie; these circumstances I deemed it only right to
apply to Dr. Swan, and to reipteit that he would enable
Inc t atl;ml to parties who, in their replies to my prey i.,us
communication, had made inquiry us to varicus matters
of de tail, such information or advice as his presion‘ ex-
perience might enable him to offer. His reply appears
to me to contain a numbvr of suggestions, the lostnfest
importance of which will, I trust. appear to you a suffi-
cient l...iteuse for my request that it !nay also be given to
the publi.4 through the medium of your columns. It is
a" follows:

"Conege, Donegal, sth March, 1817.
" Dear Sir,-Accept my thanks for your letters, as
well as for the trouble you have taken with mine of the
6th tilt , to the Council of the Royal Dublin Society.
" The privations and sufferings I have witnessed in the
discharge of my duties as a dispensary physician for the
last three months, have made me most anxieu-e if pos-
sible, to fix the attention of scientific gentlemen on
this mornenteus subject, as nothing can be more cer-
. tain than that an el?etrie state of the atmosphere,
whatever may be the peculiar p:iase of that electricity,
is the cause of the potato blight. Indesni, its pro-
tection by metallic tractors, ad in my experiment, though
badly teijested to accomplish that end, places this
beyond a doubt. On this principle the various forms of
decay in the Nato can be setistacterily explained. The
total deetruc ion in the ground, its ecc:ty after being
taken up and stored away apparently sound, as well as
the rotting of the seed in the ground, are attributable to
the injury dustain,d from this active agent by the vital
prineiple of the tuber prior to its detachment ftora the
pare. t stem.
" In my letter to the Royal Dublin Society, I merely
gave a statement of theeresult of an experiment, conclu-
sive as to this, but instituted, as you are aware, for a very
different purpcse. I declined, however, giving an.)
directions fir the protection of the growing crop, think.
ing the matter would be taken up by persons more cow•
petent than I am, but acquiescing in the wish conveyed
to me by your letter that Ishould do so, I beg with great
deference to suggest—
"First—That uncut potatoes, when the bud first ap-
peared, should alone be used for seed ; fur when the
vital energy of the pocato is affected, which it may be,
without evidencing by any external mark the existence
of disease, it will he unable to recover the shock of so
large a wound as is made by cutting the seed, or to re-
produce a bud when broken.
" Secondly—The seed should be brought covered to
the ground, and earthed up the moment it is dropped,
that it may be as little expoacd to atmospheric agencies
as possible ; and
Thirdly,-7-Before the stem rises to the surface, poles,
twelve feet high, and ten yards apart, should be erected,
with a strong three pronged wire (copper if you wish),
the prongs projecting eighteen inches from the top, bent
outwards for that -length, and the principal wire con-
veyed from them down the pole into the ground. - It is
not material that they should be placed in line with the
magnetic meridian, as Mr. Cooper, who has honoured
tny letter with his notice, seems to think the horizontal
wire unnecessary, but he approves of, and recommends,
this plan, and his opinion is of the utraost importance,
as no geoilernln stands higher in the seient tic ....odd.
This will be sufficient to divert the electric matter from
the plant in arty state of the atmosphere, hciveyer highly
charged.

"The whole sulject opens a wide field for investigl-
too, as there is every reason to believe that electricity
performs a more important part in the vegetable eco-
nomy than is generally supposed. I have little doubt,
however, from the notice taken of the trifling hints I
have given, by gentlemen of the first scientific attain.
meats, that the question, as far at least as relates to the
potato blight, will, ere January next, be thoroughly I
Inverigated. _

"Believe me, dear Sir, &c.,
"JAMES SWAN.

" John M4lfullen, Esq "
The universally admitted importance of the subject is
the only excuse I can offer for so large a trespass upun
your space ; but I cannot conclude without urging
upon public attention the vast value of Dr. Swan's sug-
gestion, that no potato should be used for seed until it
should have been first ascertained that it still contains
the principle of vegetable life, and should, for the pur-
pone, be so placed as to cause, at least, the appearance
9T a bud. Had proper attention been paid in this respect,
it seems scarcely possible that so large an exent of the
teed planted in the autumn of last year should now be
rotten in the ground and total!' lost.
I am, Sir, your f.,;! hful servant,
Grand
Canal non JOIIN .m.:...ur.LEN.
,f. ‘l7 il Ham - , treot. March 12, 1847.
A letter froni-C-1-al—a'tz, of the iith ult., says—" Prom
want of ship% Only
1 _
le ua ral y
gluedi '
tread
t' ,
rl/11,
cial
,33:.
here
at the
end
of
thea email portion of the corn collectea
n,,the Ports of the Danube are
setreitily the tnagazin 4
ot t. Y
,e,;l r has been embarked, and con-
Places
eLnowt ttteGalatz,
Still quite full The cuttotit--
of Which I,loo,oooeVimaated at less than
ears wheat, 500000
Giurgewo, Ibrail
Staten: and other
2.000,000 hectolitre,
Gexitpuegeete,,do,teanrr
tehhe, corn of the
maize, 300,000 barley, and 100 m° rye.
nlasextti:a thisreSpt irnt, 3llb°rldal,viaandis
be altogether 2,976.000 hectolitres, e,omprising nalit;tes. will
Adding to these quantities the 2,000,000 hectolitres
arrived at the peas, i•.; will be seen that western
will find here the means of supplying herself from the portsP:;
the Danube after the next harvest with nearly 5,600,000
hectolitres of corn. The Danube is at this time covered with
„kitt, and more thau 100 vessels ready laden are detained, but
at. the first opportunity, which carnet be now long in
'wing, they will take their departure for their respective
'aeons."

THE POTATO —ELECTRIC
AGENCY.
(From Saunders's News Letter.)
TO THE EDITOR OF " SAUNDERS'S NEWS LETTER."
Sir,—Aly attention was very powerfully drawn to a
letter addressed by Doctor danies,Swan, to the Council
of the Royal Dublin Society, dated Cottage, Donegal,
6th Feb., 1847, submitting to the Council the result of
an experiment with reference to the blight in the potato
crop which, under existing circumstances, and especially
at this peliod of the year, appears well deserving of the
moat serious consideration, and to which, with your
permission, I e ill again seek to draw public attention.
A copy of this letter appeared in your paper of the 16th
alt., but as a very distinct and close reference to the de-
tails of the experiment as then given is necessary to a
thorough apprehension of what is to follow, I would beg
the favour of your re-printing the following extract from
it. After a short introductory observation, Doctor Swan
proceeds—
" Having read an account of the application of elec-
tricity as a stimulant to the growth of plants, by Dr.
Forster, and others, I, early in April last, marked oil in
my garden (a rich loamy soil) an oblong plot of ground,
due north and south, containing twelve ridges of the
usual width. Into the four corners of the plot I drove
wooden pegs, and had a fine iron wire stretched from
peg to peg, and buried six inches tinder the surface, so
as to surround the plot. Poles, eight feet high, were
then placed in a line due north and south, seven yards
apart, down the centre of the plot, and a wire carried
from the centre of the buried wire, on the north, over
the top of the poles, and attached to the centre of the
buried wire on the south side, and left to collect the
electricity of the atmosphere, and convey it to the plot
beneath.
" The ground was planted about the 20th of April
with early Scotch red potatoes, without manure; and
twelve ridges to the east, planted with the usual quan-
tity of mixed manure. Both seemed equally healthy
and luxuriant in the month of July, from which I quite
lost thought of them, owing to the total destruction of
the rest of my potato crop, until the end of November,
when, to my utter astonishirent, a better or more pro-
ductive crop of sound, mealy, largo potatoes, without
the least appearance of rot, .I have never seen dug,
though nine of the twelve mueured ridges outside the
- enclosure were totally destroyed; the three next it
having a few small sound potatoes.
" 1 h a fact I look on as worthy of consideration; not
that electricity is likely to become a substitute fur
manure, but as it tends to show that disease in the
potato crop of the ,past year was owing to atmospheric
influence, and not, as so generally believed, to the de-
predations, in the firet instance, of animdculue, which are
the consequence; not the cause, of decay."
l'he letter concludes by an expression of the writer's
conviction of the efficacy of conductors, properly ad-
justed, in preserving tne potato from blight, and his in-
teetien to plant mote largely under their protection
daring the present season.
Early tastes end pursuits had led me a good deal into
the wide and interesting field of chemical reading and
research, sad nowhere in the course of my application
to it bad my attention been so much interested as by the
well ascertained proofs of the extraordinary influence of
electricity, in reference to the economy both of
animal and vegetable life ; and in turning my thoughts
—and who has not done so ?—to the probable cause
of the blight in the potato crop of the two last years,
I was irresistibly led to the conclusion which the re- -1
sult of 1)r. Swan's experiment has gone, in my opinion,
a considerable way to verify. Under these circum-
stances it will not seem strange that upon the appear-
ance of his letter I was strongly impressed with the im-
portance of the result of his experiment, and which was
rendered the more interesting from it, peculiar cir-
cumstance that the result aimed at, the application of
electricity as a substitute for manure, v, as not that which
was fortunately realised—namely, the preservation of
the root or tuber. I had in consequence a few hundred
copies of the letter printed, and distributed pretty freely
among the landed proprietors and agriculturists.of the
adj scent counties, and 1 had the gratification to find my
euminunication very promptly responded to by several
highly respectable and influential persons. I was,
amongst others, favoured with a letter from Sir
Gerald Aylmer, who, as many of your readers
cannot fail to be aware, is a very extensive landed
proprietor in the edjseent county of Kildare, and a'scien-
titic practical agriculturist. In the letter Sir Gerald
states, and I have his permission to mention the circum,
stance upon his authority, that ho had long previousl3
arrived at the conclusioa that the potato blight of the
last and preceding year was attributable to the effect
of electricity ; that under this impression he had,
iu the spring of last year, had a ridge ,of the
usual description piloted close along side of a wooden
pa:ifig, the upright slabs or pieces of which `acre
bound together a, the top by an iron hoop fur its
enlre length, arid which he resvonahly assumed would
act as a coneucter this ridge, when dug out, there
was net is sine le unsound potato, although his crops in
all otter places suffered ia the same way as those of
his ne•ghbours. From the Messrs. Rats, of Rath-
moyle, in the earn° county, who are admittedly the moat
extensive growers of the potato in this country, their
crop of laet year having been, as I am aware, little
short of 130 acres, I had a similar communicati3n,
stating that their experience and Observation had quite
led them to agree in the opinion that electrical agency
was the immediate cause of the late blight of the
potato, and thlt they had determined to try the effect
of con4uctora placed over their crop of this year ; and
4 in several other communications from highly respect-
able persons, I found a general concurrence in similar
e.piniene.