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bitants, and suffered to wither on the shore, either through ignorance of its quality, or their fear of eating any herb that has not found its way into either the market or the garden. As it is a perennial, it cannot fail of being a valuable addition to the gardens of those who have residences near the sea. It should be sown on a heap of decayed sea-weed, co. vered with large gravel or small flints. The root is of the tap kind, but often branches among the stones on the beach; it is sweeter than even the carrot. The flowers are formed of five petals of a pale green colour, but of so solid a nature, that when expanded they cannot be closed without breaking; but to counteract this apparent inconvenience, and to secure the pollen from the weather, to which from its natural situation it is particularly exposed, each petal forms a kind of hood.

On promoting the early Puberty of Apple and Pear Trees when raised from Seed, by J. Williams, Esq. Many persons inclined to become experimentalists in raising fruit-trees from seed, with a view of obtaining new, improved, and more hardy varieties, have been deterred from the attempt by the great length of time requisite for ascertaining the result of their industry; for the appletree, when raised in the common way from the kernel, rarely affords its first blossom before it is eight or ten years old, and the peartree requires even a longer period, twelve or fifteen summers often elapsing before the leaves of seedling-trees are capable of forming their first blossom-buds. In No vember and December, 1809, I sowed the kernels of several ripe

pears, in separate pots, and placed them in a green-house during the winter. They began to vegetate in the following month of February, and in March the pots were removed into my grapery, where they remained till after Midsummer. The plants were then carefully removed into a seed-bed, and planted in rows, about fourteen inches apart, where they remained till the autumn of 1811, when they were again transplanted into a nursery, at distances of six feet. Every succeeding winter I pruned away all small trifling lateral shoots, leaving the stronger laterals at their full length to the bottom of the plants, and made such a general disposition of the branches, as that the leaves of the upper shoots might not shade those situated underneath; every leaf, therefore, was thus rendered an efficient organ, by its full exposure to the light. At the height of about six feet, I had the satisfaction to observe, that the branches ceased to produce thorns, and the leaves began to assume a more cultivated character. Several of these trees afforded blossoms and fruit last year. One seedling Siberian variety of the apple, thus treated, yielded fruit at four years old, and many more at the age of five and six years.

The Golden Pippin. Mr. Phillips, of Bayswater, who has lately written an historical account of fruits, tells us, that there are at this time a considerable number of the true golden pippin trees growing on the mountains in Madeira, about 14 miles from the capital of that island, and at an elevation of about 3,000 feet above the sea, which regularly

produce abundance of fruit, not withstanding the trunks and branches are covered with a white lichen or moss. Grafts which were sent from these trees by Thomas Harrison, esq. about three years ago, produced fruit at Cheshunt in Hertfordshire the second year, and proved to be the original golden pippin.

In several parts of America these trees are in a thriving state, which has been proved by the excellent quality of the fruit lately sent to this country. In addition to which he tells us he saw, notwithstanding the late unfavourable season, many trees of this variety in Sussex, as healthy

in appearance as most other kinds of apples, particularly in the garden of Messrs. Humphreys, at Chichester, where the fruit was of a size and perfection that he had never seen surpassed.

Mr. Phillips admits that the golden pippin is a more delicate tree than many other varieties, but by no means so much so as is generally supposed, and it only requires, as it deserves, the most genial situation of the orchard to render it as prolific as formerly. About the year 1685 lord Clarendon had, at his seat at Swallowfield, Berks, an orchard of 1,000 golden and other cider pippins.

ARTS AND MANUFACTURES.

New Style of Engraving on Copper. THE new style of engraving upon copper, which Mr. Lizars has invented, is a substitute for wood-engraving, in the same manner as lithography is a substitute for copper-plate engraving; but while Mr. Lizars has given us a cheaper art for a more expensive one, he has also given us a more perfect art for one which is full of imperfections. The invention of lithography, on the contrary, was the substitution of an imperfect for a perfect art, and whatever progress it may yet make, we can never expect it to exhibit that union of bold and delicate touches by which strokeengraving is characterised.

In wood-engraving, all the white parts are cut below the general surface of the wood, while VOL. LXIII.

all the black lines, which constitute the picture, are left on the level of the general surface. Hence it is impracticable to hatch or to leave upon the surface of the wood elevated lines, which cross each other, without cutting out the small white lozenges, which would be a work of immense labour, and by no means perfect, even if it could be accomplished. All the shadings, therefore, in wood-engravings, are formed by parallel lines, which never cross one another. In copper-plate engravings, on the contrary, all the black lines are cut below the general surface, while the white parts correspond with the general surface of the copper. The art of hatching is therefore extremely easy in this art, and we have only to cross the lines 2 Z

cut out by the engraver in the same manner as we do them in drawing with the pen.

These observations will prepare the reader for understanding Mr. Lizars's invention, and for forming a correct estimate of its value.

In the operation of engraving, the desired effect is produced by making incisions upon the copper-plate with a steel instrument, of an angular shape; which incisions are filled with printingink, and transferred to the paper by the pressure of a roller, which is passed over its surface. There is another mode of producing these lines or incisions by means of diluted nitrous acid, which is well known, and in which the impression is taken in the same way. The new mode of engraving is done upon a principle exactly the reverse; for, instead of the subject being cut into the copper, it is the interstice between these lines which is removed by diluted acid (commonly called aqua-fortis), and the lines are left as the surface, from which the impression is taken, by means of a common type printing press, instead of a copper-plate press.

This is effected by drawing with turpentine varnish, coloured with lamp-black, whatever is required upon the plate; and when the varnish is thoroughly dry, the acid is poured upon it, and the interstice of course removed by its action upon the uncovered part of the copper. If the subject is very full of dark shading, this operation will be performed with little risk of accident, and with the removal of very little of the interstice between the lines; but if the distance between the

lines is great, the risk and difficulty is very much increased; and it will be requisite to cut away the parts which surround the lines with a graver, in order to prevent the dabber with the printing-ink from reaching the bottom, and thus producing a blurred impression. It is obvious, therefore, that the more the plate is covered with work, the less risk will there be in the preparation of it with the acid, after the subject is drawn; and the less trouble will there be in removing the interstice (if any) from those places where there is little shading.

A great degree of facility will be obtained by etching out the first line with the common etching-needle, and afterwards putting on the cross-line with the varnish; and by this means there will be much more variety, regularity, and beauty in the effect, than if the whole had been done with the varnish.

Although this discovery must still be considered in its infancy, and very incomplete, yet it is probable that much may be done with it, if proper materials can be found out to work with. It possesses every advantage which common engraving does, and at the same time all the advantages of engraving on wood; and, above all, it enables us to procure as many impressions as can be taken from types. The greatest difficulty to be surmounted is, to obtain a substitute for the varnish which will flow from a pen or pencil like Indian ink; for as the varnish has a tendency to dry, and get tough in the pencil, the operation is by this circumstance very considerably impeded. Other substances than copper may be

used; and experience may prove them to be better adapted to the purpose. Wood covered with white lead and strong glue, has been tried, with considerable success, but not so much as copper; and it may be as well, for the sake of those who may think it worth

their while to make other trials, to mention, that lead, pewter, type-metal, zinc, and brass, have all been used with various success, but copper has been still found superior to them all.Edinburgh Philosophical Journal.

ROCKET EXPERIMENTS IN INDIA.

The following is an Account of a Practice lately made in the Presence of the Governor-General, at Calcutta, under the Direction of Captain NICHOLSON, Superintendant of Rockets in India: the India Company having established Rocket Corps in each of the Presidencies, from the Plans and Instructions, with Rockets and Apparatus, sent out from this Country by Sir WILLIAM CONGREVE:

Round.

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10

Report of Rocket-Practice at Calcutta, June 11, 1821.

Struck.

2 yards left of target.
1 ditto right, ditto.
Through the target.

2 yards to right of target.
5 ditto, left ditto.
1 ditto, right ditto.
3 ditto, left ditto.
1 yard over target.
Through the target.
Over centre of target.
3 yards to right of target.
Through the target.

Rockets.

Yards.

1st with... 6 pdr. ditto

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Over centre of target.
Through the target.

Ditto.

Ditto.

Good direction.

1 yard to right of target. Through the target. Ditto.

A ground volley of ten 6-pounder rockets, at 500 yards from the target; an excellent close volley, most of them through the target. These rockets were merely laid in the proper direction on the ground, and fired without any apparatus, making in all at least 16 rockets through the target; and, indeed, viewing the whole of this prac tice, it may be fairly stated, that it could not be excelled by the best artillery.

Application of the Congreve Rocket in the Whale Fisheries.The ship Fame has returned to Hull, and captain Scoresby has confirmed all that was stated in his letter of the 24th of June, inserted in some of the public papers in July last, respecting the important advantages to be derived from the use of the rocket in the whale fishery.

The Fame has brought home nine fish, in the capture of the whole of which the rockets were successfully employed. After being struck by the rocket, the largest whale became an easy prey to its pursuers. In one case, instant death was produced by a single rocket, and in all cases the speed of the fish was much diminished, and its power of sinking limited to three or four fathoms.

One of the largest finners, of 100 feet in length, a species of fish seldom attacked by the ordinary means, and of the capture of which there is scarcely an instance on record, in the northern seas, was immediately tamed by a discharge of rockets, so that the boats overtook and surrounded it with ease.

Six out of the nine fish died in less than fifteen minutes; and five out of the number took out no line at all. One only survived nearly two hours, and one only took out more than a single line, by getting into a pack of ice, where the boats could not follow. The peculiar value and importance of the rocket in the fisheries is, that by means of it, all the destructive effects of a six, or even a twelve-pounder piece of artillery, both as to penetration, explosive force, and internal fire, calculated to accele

rate the death of the animal, may be given with an apparatus not heavier than a musket, and without any shock or re-action on the boat; whereas it is obvious, that no boat applicable to the fishery of the whale can ever be made capable of sustaining the shock necessary to produce the same effects as the six or twelve-pound shell, by the ordinary means of artillery, or any thing in any degree approaching them.

In fact, nothing larger than the harpoon gun could be applied; and the missile which could be discharged from such an implement, could neither have penetration, nor explosive force, sufficient to do any serious injury to the fish.

With respect to the rocket, however, it is a fact that some of the smallest fired in the late experiment in the Fame, penetrated completely through the body of the fish, so that the effect of the explosion was visible on the opposite side-the fierce fire of the rocket fixed in the animal's inside, rapidly destroying life; and the effects, and report of the explosion, being distinctly perceivable within him, in one instance above stated, producing immediate death. Indeed, it is certain, that this might, in almost every case, be insured by increasing the power of the rocket, without increasing the inconvenience or incumbrance of the apparatus required to discharge it, and with as little re-action on the boat, as when the smallest rockets are used. In addition to this, it may be stated, that there is no doubt of the rocket ultimately dispensing with the operation of the hand harpoon, by conveying

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