the liber of the leaf; this fluid may be easily precipitated by simply placing, in the autumn (previously the vessels are so small that they are choaked up by the precipitate), a shoot of the vine, in a weak solution of the sulphate of iron and, upon standing therein for some time, the thin parts of the leaves will become black, as soon as the union takes place between the ascending sulphate of iron, and the gallic acid of the leaf; it will afterwards descend down the vessels of the liber of the stalk of the leaf, and sometimes down to the liber of the collet, which will in like manner become black: but the ascending vessels of the alburnum of the shoot will not be discoloured, nor the ascending vessels of the stalk of the leaf, because the solution has not met with any gallic acid in its ascent through those vessels.

It is highly gratifying, in our examination of the economy of Nature, to have her assistance in such operation; for no artificial means could have been used to pass a solution into the above minute vessels had they been void of actual life.

By the assistance of these chemical tests, I flatter myself the investigation of the anatomy of vegetation will be facilitated, and I sincerely hope others will prosecute it with greater perseverance; by so doing they will convince themselves how sublimely Nature carries on her grand operations, by a repetition of parts, and those united by the most simple means, as well as by a continuation of those parts subdivided. Although we shall never discover the hidden springs by which she creates, animates, and elongates the living vegetable fibres; yet, by their aid, many interesting facts may be discovered relative to the larger vessels. I have many apologies to make for occupying your time, even in the perusal of this long letter; and I am fearful, also, in addition to the reasons already given of the number of drawings, that the length of my remarks will exclude both from your valuable and instructive Magazine; but this I must leave entirely for your liberality and consideration. I remain, Sir, &c.

Bath, June 12.

WALTER WILLIAM CAPPER.

The common copperas, or sulphate of iron, becomes a stronger test by the following method:

Dry down before the fire, on a plate, 8 oz. of the common copperas of the shops. Reduce it to a fine powder, then weigh 100 grs. of it, which place in a mortar, and add to it 10 drops of nitric acid, mix them well together, afterwards add 4 oz. of water, and filter it. This liquor should be kept closely stopped.

The following is a description of the little regulating machine (fig. 6.), by which thin slices may be cut from the collet, &c.

abcd, The top 1 in. square,

and a quarter thick. e f g h, Another of the same size and thickness, but of an octagon shape, ik, A cylinder 4 in. long. which connects the above two together, leaving a round hole at the top, of half an inch wide. Im, A movable core 21 inches long, covered top and bottom; it is to be put into i k. o, The screw about 1 in. long or more.

P, A square knob fastened

to the screw o.

q, A cork with a circular hole on one side.

T, A collet of a vine, a little longer than the cork 4, and to be placed within it.

st are the same as qr, but now supposed to be placed in the hole of a b cd. They are to be pushed down, leaving ta little above the surface, which is to be cut off with a flat-bladed razor. Then carefully turn the screw an eighth round, which will raise the collet sufficiently to enable you with the razor to take off a thin slice.

The whole is made of brass. This machine I invented, but Mr. Cary in the Strand, London, will make others, as he has seen mine, and I shall be obliged to any person for any improvement upon it.

W. W. C.

1

d

6

b

f

h

ART. III. Notes on the former and present State of Horticulture in Ireland. By Mr. JOHN ROBERTSON, F.H.S.

Sir,

I SEND you the following memoranda, partly taken from an article entitled "Dubliniana" in the Pilot newspaper of November 9., and partly my own remarks on the memoranda, and on the former and present state of horticulture in this country.

"The Use of Sea-kale as an esculent Vegetable is supposed to be of recent date, and was first introduced, as has been said, by the present Bishop of Carlisle, who cultivated it in his garden for asparagus; but, so long ago as the year 1764, this plant was cultivated in the gardens of Dublin, and the seeds sold in the shops. When the seeds were sown, they were covered over with gravel; the shoots were used in spring, as they are now, and preferred to any other species of kale. It was the practice, however, to boil them in two different waters, to extract the salt, with which the plant was supposed to be impregnated, from its marine origin. The valuable The valuable property, also, which distinguishes it from other kales, that the root is perennial, and will bear cutting for forty years, was well known. (Tutty, vol. i. p. 4.) The sea-kale grows at present, in great abundance, on every part of the sandy shores around the bay of Dublin, and is cultivated in every garden in and near the city.

"Pine-apples were first brought to Dublin by a man of the name of Buller, who, in the reign of Queen Anne, settled in the vicinity of Dublin, and held an extensive nursery in New Street, where traces remain of it to this day.

"In the reign of George I., the Hugonots established a Florists' Club, for the purpose of promoting the cultivation of flowers, and held their meetings at the Rose tavern, Drumcondra. They were continued until the reign of George II.; but the science of gardening was, from that time, entirely neglected, until a number of the principal gardeners, in the vicinity of Dublin, assembled at the Rose tavern, Drumcondra, on Sept. 30. 1816, and formed themselves into a Horticultural Society."

The writer must have been misinformed when he says that pine-apples were introduced to Dublin in the reign of Queen Anne. They were only cultivated in England late in that reign, for the first time. If introduced first to Dublin by Buller, it should have been the reign of George II.: there were but two nurserymen of that name there in succession. I recollect having seen the younger Buller myself, at his seedshop in Pill Lane, about the year 1776. The elder was in

business about 1756, as my father purchased from him, then, a stock of pine plants, perfectly clean and free from insects: and it may be worth remarking, as rather a rare instance of any such pedigree, and so remote, that from that stock has descended to me the one which I am at present in possession of equally free from insects, and that solely by guarding against their intermixture with any other: perhaps the only effectual way of preserving pine plants clean, notwithstanding all the nostrums that have been recommended.

However horticulture may have been neglected about Dublin at the period mentioned by the writer, it is not to be taken for granted that it was so in other parts of Ireland. Kilkenny, at least, forms an exception, as it never was so flourishing there as then.

Drawing a radius of ten or twelve miles round that city, you would, to my knowledge, for twenty or thirty years from 1785, reckon within the circle a dozen gardens or more, each of which contained pine-stoves, from 50 to 100 ft. in length; and other forcing-houses corresponding *, well stocked and managed by able gardeners from Kew, Hampton Court, and other places of note round London. Now we cannot count half the number: the Union has rendered some of our great landed proprietors absentees; and the fall of lands and prices has disabled others, and has swept off a number of landholders, who were rapidly improving the face of the country by building, farming, planting, and gardening: so that horticulture in Ireland, as far as my observation extends, was never at so low an ebb as at the present moment. I am, Sir, &c.

Kilkenny, Nov. 1829.

JOHN ROBERTSON.

ART. IV.

Outlines of Horticultural Chemistry: — Diseases of Plants. By G. W. JOHNSON, Esq., Great Totham, Essex.

(Continued from Vol. V. p. 409.)

THE following sketch (fig. 7.) represents the apparatus I have found the best for ascertaining the retentive power of soils. a represents a small lamp; b, a tripod for supporting a small tin

As an instance,: fifty years ago the present Dowager Countess of Ormond had her table regularly served, through the winter with cucumbers raised in her pine-stoves on treillages against the back wall; though, only the other day, Mr. Aiton, the king's gardener at Kew, had a medal presented to him by the Horticultural Society, for the introduction of the practice about

7

vessel c, which has a small hole and plug at g, for the purpose of filling it with water; and a small pipe d, for the escape the steam when the water is brought to a boiling temperature; h is a small pair of grain scales. To ascertain the moisture retentive power of a soil, put 10 grains of it, previously dried by exposure to a temperature of 212° (the boiling point of water), for half an hour, by having it laid upon c, whilst the water within it is kept boiling for that period. On the 10 grs. of

previously dried soil put, by means of a small quill, three drops of clean water; ascertain the exact weight of these, usually 4 grains; then suspend the beam, so that the pan of the scales containing the soil may rest upon c, as represented in the sketch, the weight of the water having previously been removed from the other scale-pan f. The water in c must be kept boiling, and the exact number of minutes noted that is required to evaporate the added moisture, so as to return the beam into equilibrium. It was by means of this apparatus that I obtained the comparative results detailed in a former volume. I have always found those soils proportionably unproductive, the first from containing too much alumina, and the second from a redundancy of silica, as they required more than 50 minutes, and less than 25 minutes, to deprive them of half their weight of moisture.

ease.

I shall now proceed to consider some of the diseases of plants, whose ravages affect the horticulturist, and on which science may afford some light. Plants being organised bodies, whose parts, in the common course of nature, are subject to waste and decay, the functions of these are consequently liable to disarrangement, and such disarrangement constitutes disSuch morbid affections are not, however, always the consequences of old age: they are often caused by matters being absorbed from the soil which are inimical to the constitution of the plant; from a want of those that are beneficial, as well as from their excess; from violent and sudden transitions of temperature; from wounds, and from the attacks of vermin. "Animals," said the late Dr. Good, " are liable, as we all know, to a great variety of diseases; so, too, are vegetables, to diseases as numerous, as varied, and as fatal; to diseases epidemic, endemic, sporadic; to scabies, pernio, ulcer, gangrene; to polysarcia, atrophy, and invermination. What