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and multiply and get matted around them, which of itself must greatly assist. Whether the roots are impatient of too much moisture, or attracted by the gases absorbed as they cling round those charred pieces of wood, and of clay as in pieces of pot and brick, or whether opposite states of electricity may affect, it might be difficult to say. It is likely, however, that the absence of undue moisture, and the presence of a proper quantity of gases, form the principal cause. I have seen them cling round large pieces of porous bones with avidity, while they refused to enter the powdered small pieces of bones, where, perhaps, there was too great an abundance of food, the ends of the spongioles appearing diseased and swoln. The carbon of the ashes is also undoubtedly given off as the pieces begin to dissolve. I have seen such powder to increase greatly to appearance the growth of hyacinths in water, as compared with those in pure water; and the saline substances and carbon were likely to afford most of the benefit there.

To enable us to arrive at correct data, plants should be analysed in the various stages of their existence. The comparative analyses of plants must vary according to the age of the plant experimented on ; according to the part of the plant examined also, if in portions; perhaps, also, according to the liberality of the supply furnished to the roots. What is to be allowed for constituents, and what for assistants, and what perhaps deducted for superfluity, may be very difficult to solve, and may require many analyses of scientific men, and much judicious observation of practical men, before arriving at correct principles. Superfuity is undoubtedly prejudicial; and it has been frequently proved by experience, that plants will at times absorb both more water and more food in the water than are necessary, or than the leaves can elaborate, so as to enable the organs to assimilate. As the quantity of food absorbed depends partly on the quantity of water absorbed, excess in some seasons and some soils may more readily occur than in others. In seasons when little light is present, less water is, however, absorbed, though the season should be more wet and the ground more moist; and, to a certain extent, the one is a corrective of the other: yet confusion may arise from the confliction of causes, and may baffle and retard the efforts at establishing rules ; though, if we are cautious of deceiving ourselves and others with preconceived notions, and do not attempt to make practice bend to theory, it will undoubtedly in the end conduct us to the right path.

In endeavouring to ascertain from practice the necessity for these substances, by the effects produced by their application, the recorded effects of experiments are much at variance. Nitrate of soda has been found to have very different effects in different situations. This has been ascribed to the places in which it failed being near the sea coast; and, the lands abounding in salt (muriate of soda or chloride of sodium), they had therefore no need, it is said, for nitrate of soda, and hence the want of effect. At Roselle, which is so near the sea as to entitle it to the benefit of a saline atmosphere, and where common salt was found to produce no effect which might be ascribed to that cause, nitrate of soda was found to produce a powerful one.

Yet even here it was found by the gardener that a small quantity killed the stool plants of sea-kale, while, at the Society's Experimental Gardens, it has been given in doses of 1 lb. to the plant with good effect. The nitric acid of the nitrate when absorbed must have a different effect from the muriatic acid or chlorine of the other. The latter are seldom found as constituents in plants, and little is known of their beneficial action; while nitric acid has been found by Braconnot to produce fibre from starch, and, if confirmed by further experience, may be found in this way to assist in performing an important part in the vegetable economy. It is also said to assist in the formation of oxalic acid, which last is thought to abound more in plants than analysis points out; the oxalate of potash being changed into a carbonate in extracting it. Like ammonia, nitric acid probably assists also, by the nitrogen it contains acting as a stimulus to growth: probably ammonia is formed from it, as it is generally found to give rise to a dark green colour, denoting the alkaline state of the chromule, an appearance which generally betokens vigour of growth, but is sometimes found to appear without this increase. When a sufficient dose of manure has been given before the dressing of nitrates, they have been often found to produce no additional effect. At Caprington this season, a lot of potatoes had been manured at the rate of about fifty cubic yards of well rotted manure (about thirty tons), and the crop produced was about twenty tons per acre, the manure and working of the land being excellent: but some drills, dressed with the usual quantities of nitrate of soda, sulphate of soda, and urate containing a great deal of ammonia, had no perceptible increase; apparently from the large quantity of ammonia supplied by the manure to a crop not carrying off much nitrogen, the substances containing it had no effect. Some nitrate of soda and sulphate of soda, sprinkled on a crop of vetches in an adjoining field, caused a great increase of produce, showing that there was nothing naturally in the soil against their acting. The many causes noticed in the commencement of this essay may have occasioned different results, and may not have been observed. Sometimes the substances lie over year in cold soils and cold seasons before producing effect; and some may have been applied unwittingly to pieces of fields which were inferior, not suiting the season. One part of the field, equally good with the other and as well manured, may fail also from tids of weather being against it, one piece being worked on a dry day, the other on a wet; one piece or one field being farther advanced than another, and not suffering so much from drought as the other, the soil being more retentive in one place, and more open and porous in another. If all these are not properly taken into account, the observation is imperfect; and some of them may, from circumstances, have eluded the observation of the most vigilant. There must be causes for every thing, but we must wade through much difficulty in arriving at them before we can furnish proper data, and must not expect mathematical results where so many obstacles, seen and unseen, are in the way

The best experiments for ascertaining the true nature of the action of these substances are those made by Mr. Fortune in the Society's Experimental Gardens. He washed silver sand as a soil for plants, to prevent any effect from previous organic remains; and also washed the roots of the geraniums he planted in the sand. The result was, that none of the various substances he watered with in solution had any more effect than common water, except carbonate of ammonia and wood-ashes mixed, which contain the most of the constituents generally needed in plants. In some potted in common soil, the other substances produced the usual effect. Before any action can take place, it is evident that real food containing all the constituents of plants must be supplied from some source, and these substances will always be most generally valuable. Such as sulphuric acid, which is found only in very small quantities, unless in some particular kinds of plants; and such as muriatic acid *, of which only a trace is to be found; must be much less needed than carbonic acid, and must act principally by their influence on the constituents of food, either in the soil before absorption, or in the transformations going on in the plant. Suchbases as iron are prejudicial, unless in very small quantity; such as magnesia and alumina are very little needed as constituents, and must be sometimes hurtful in excess. Potash

The experiments of Mr. Solly on muriatic acid, lately recorded in the Gardener's Chronicle, show that, so far from being injurious, as formerly supposed, and poisonous to plants, he found it beneficial, even in pretty large quantities. He found it, also, to have the effect of requiring much less water to the pot the plant experimented on was growing in the usual perspiration of the plant being much checked, either by the stopping of the pores, or preventing the extrication of water chemically. Some pots naturally require much more water than others, but this is likely to have been observed. Acids, generally, are prescribed to check perspiration in human beings ; if acids have the same effect on plants, it may be found another circumstance requiring attention. Such an action cannot, certainly, be generally beneficial.

3d Ser, - 1843, I.

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is most prevalent in all parts of the plant, and should, therefore, be most beneficial. Lime is found in greatest proportion in the stem, and should be most beneficial to the growing plant. Soda is found most in seeds, and should be most useful at the time of ripening. It is evident, also, that such as soda cannot be so much needed, as a constituent, as potash; though, as a solvent, it is more powerful. Nitrate of soda has been very beneficial to onions this season ; its deliquescent property of extracting water from the air may be useful in a dry season. As a knowledge of these things spreads, it may conduce to economy to employ them only when needed; and the object of fruitfulness may be secured at much less expense.

Art. II. The Roller called Pica marina in Italy. By Charles

WATERTON, Esq.
“ I love to see the little goldfinch pluck

The groundsel's feather'd seed, and twit and twit;
And then, in bower of apple blossoms perchd,
Trim his gay suit, and pay us with a song.

I would not hold him prisoner for the world.” HURDIS. I KNOW nothing in the environs of Rome half so grand and charming as the ornamented grounds of the beautiful villa Pamphili Doria, the gates of which are always opened to the public. A blessing be upon the head of its princely owner, for this prized permission to the world at large! May his liberality never suffer by the hand of wanton mischief, or ever be checked by the presence of a rude intruder! Many a time, when fairly tired with the never ending scenes of painting and of sculpture within the walls of the eternal city, have I resorted to this enchanting spot, here to enjoy an hour or two of rural quiet, and of purer air: and, could I have had a few British gardeners by my side, the enjoyment would have been more complete; for gardeners in general are choice observers, to them

“ Not a tree,
A plant, a leaf, a blossom, but contains

A folio volume.” The marble fountains of Pamphili Doria, its lofty trees, its waterfalls, its terraces, its shrubs and flowers and wooded winding-paths, delight the soul of man, and clearly prove what magic scenes can be produced, when studied art goes hand in hand with nature. The walk, canopied by evergreens of ancient growth, and at the end of which a distant view of St. Peter's colossal temple bursts upon the sight, has so much truth and judgment in its plan, that I question whether its parallel can be found in the annals of horticultural design. When St. Peter's dome is illuminated, whilst standing under the wooded archway of this walk, you may fancy yourself on the confines of Elysium.

As an additional charm to the beauties of Pamphili Doria, the birds are here protected, so that not one of them which comes within its precincts is ever transported to the birdmarket at the Pantheon in Rome, where individuals of every species known in Italy, from the wren to the raven, may be had, ready trussed for the spit. I myself, in the course of the season, have seen and examined the following list of good things on the stalls, to regale natives and foreigners in Rome.* Towards the close of April, the walks of Pamphili Doria resound with the sweet notes of the nightingale both day and night; and, from February to mid-July, the thrush and blackbird pour forth incessant strains of melody,

There stands in this enclosure a magnificent grove of stone pines, vast in their dimensions, and towering in their height. Here the harmless jackdaw nestles, here the hooded crow is seen, here the starling breeds in numbers, and here the roller, decked in all the brilliant plumage of the tropics, comes to seek his daily fare. But, as far as I could perceive, after two seasons

Wild boars, roebucks, red deer, hares, rabbits, pheasants, frogs, common partridges and two other species, quails, water rails, godwits, snipes, woodcocks, dabchicks, coots, wild ducks, wild geese, golden plovers, green plovers, sandpipers, wigeons, teal, gargany, brown-headed ducks, sheldrakes, tufted Grecian ducks, green linnets, goldfinches, brown linnets, grosbeaks, land tortoises, ringdoves, rock pigeons, fancy pigeons, wagtails, robin redbreasts, common buntings, grey buntings, cirl buntings, bluecap titmouse, oxeye titmouse, longtailed titmouse, blackcap titmouse, cole titmouse, blackcap sylvia, song thrush, blackbird, blue thrush, jays, magpies, rooks, hooded crows, hedge sparrows, hawks, siskins, common larks, black-throated larks, titlarks, smaller larks, judcocks, land rails, combs from the heads of cocks, fowl and turkey legs and feet, buzzards, curlews, small stints, redwings, pochards, falcons, civetta owls, whinchats, windhover bawks, kites, stone curlews, jackdaws, shoveler ducks, gobbo ducks, hedgehogs, water hens, spotted water hens, bitterns, mergansers, stormcocks, porcupines, foxes, goats, kids, yellow wagtails, fieldfares, hooting owls, horned owls, barn owls, wheatears, redstarts three species, nightingales, yellow-breasted chats, stonechats, brown-headed shrikes, common shrikes, little terns, gulls, Guinea fowls, goatsuckers, eggs from the ovarium of all sizes, wind eggs, larger white egret, common heron, turkeys, guts of turkeys and common fowls, swifts, swallows, starlings, little bitterns, white-winged bitterns, large bitterns, bullfinches, chaffinches, water tortoises, turtle doves, water rails, shags, red-throated mergansers, badgers, lesser spotted woodpeckers, smallest woodpeckers, green woodpeckers, small white-throated mergansers, common wrens, common gold-crested wrens, splendid golden crested wrens, house sparrows, mountain sparrows, mountain sparrows with yellow speck on the throat, olive-throated bunting, crested grebes, Canary birds, hoopoes, rollers, beeeaters, golden orioles. Add to this list butcher's meat of all descriptions, and the finest fruits and vegetables, and flowers. By the custom-house report, seventeen thousand quails have entered Rome in one day.

N.B. If a man cannot get fat in this city at a very moderate expense, it must be his own fault.

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