potatoes. Of its fecula are made starch and a variety of pastry work; reduced to a pulp, this root enters into the composition of certain fermented liquors, supposed to be very proper to restore the lost tone of the stomach. In the city of Santa Fe, and indeed in all places of this kingdom where they can obtain the Arracacha, they are of full as universal use as the potatoes are in England. The cultivation of the Arracacha requires a deep black mould, that will easily yield to the descent of its large vertical roots. The mode of propagating it is to cut the root into pieces, each have ing an eye or shoot, and to plant these in separate holes. After three or four months, the roots are of sufficient size and quantity to be used for culinary purposes; but if suffered to remain for six months in the ground, they will often acquire an immense size, without any detriment to their taste.

The

colour of the root is either white, yellow, or purple, but all are of the same quality. The most esteemed in Santa Fe are those of Hipacon, a village about ten leagues north of the capital. Like the potatoe, the Arracacha does not thrive in the hotter regions of the kingdom; for there the roots will not acquire any size, but throw up a greater number of stems; or, at best, they will be small and of indifferent flavour. In the countries which are there called temperate, being less hot than those at the foot of the Cordilleras, this vegetable is sometimes found to thrive, but never so well as in the elevated regions of those mountains, where the medium heat is between 58 and 60 deg. of Fahrenheit's scale. Here it is that these roots grow the most luxuriantly, and acquire the most delicious taste. By care and at VOL. LXV.

tention in gradually inuring individuals of the Arracacha, or their seeds, to a cooler temperature, there is every reason to hope that this valuable root may, like the potatoe, (which was introduced to us from an equally warm country), be na turalized to our soil.

The Maturation of Fruit-M. Berard being convinced by a series of experiments, "that the loss of carbon was absolutely necessary for the maturation of unripe fruits, it appeared probable that they might be preserved for a long time unchanged, if they were confined in a medium in which they could not generate carbonic acid, particularly those which spontaneously ripen when gathered green. It would be sufficient for this purpose to confine them either in a vacuum, or in an atmosphere of carbonic acid, or any gas not containing oxygen. I found, however, upon trial, that green fruits, under these circumstances, give out a certain quantity of carbonic acid for the first two or three days, but not afterwards. On the 1st of October, I put a green, hard, sound pear under a small bell-glass, and exhausted the air by an air-pump. The next day the glass contained some carbonic acid, given out by the fruit, which I pumped out, and repeated this for four or five days successively, after which no more gas was generated. On the 15th of January following, I examined the It had kept perpear. fectly well, and was quite hard. I let it remain for five or six days in a room exposed to the air, during which it ripened, and was perfectly well tasted. At the same period, and with the same success, I succeeded in preserving another pear, which I had suspended in a jar filled with carbonic acid gas. These,

U*

and other similar experiments, gave me great hopes of being able to preserve fruits for a long time by the methods above mentioned, but they have not been entirely real ized. I have operated on cherries, gooseberries, apricots, plums, pears, and apples. I selected very sound fruits, within about a week to a fortnight of their natural term of ripening, and enclosed them in vacuo, others in carbonic acid, in hydrogen, or in azotic gas. All these fruits have been preserved for a certain time; but if the experiment has lasted too long, though they are still preserved from decay, they lose their fragrance and sweet taste, and they all acquire nearly the same flavour, which is peculiar, not easily described, and disagreeable. They also turn sour, and this is owing to the formation of malic acid alone. Cherries and apricots, long enclosed in jars, with out the presence of oxygen, sweat out in a few days a liquid of the colour of the fruit. If they are withdrawn after twenty days, and then exposed for a day to the open air, they retain their agreeable taste; but I found a specimen of cherries, which I examined, after an enclosure of about five months, to retain their smell, indeed, and their proper colour a little weakened, but to have lost their peculiar taste, and to have become acid, with that particular, unpleasant flavour which I have already mentioned. I have at this moment before me (December 25) a jar enclosing two peaches in azotic gas, which have remained in this situation since October 6; to appearance they would be thought just gathered, but they have lost their delicious perfume and flavour, whilst a similar sample, opened November 5, and then exposed

for two days to the air, have turned out quite good. Pears and apples are, of all the fruits that I have tried, those that are the longest preserved in a medium deprived of oxygen. I have preserved pears in a vacuum from October to the following July, which remained quite sound, but had exchanged their agreeable flavour for the sour and unpleasant taste already described. But after three months enclosed in vacuo, and a few days subsequent exposure to the air, they remain quite good in every respect. May we not hence presume, that the fruits which ripen of themselves when severed from the tree, retain this quality in virtue of a certain degree of vegetable force which remains in them, and lies dormant for a time when they are immersed in a non-oxygenous medium, but which is lost in the end, when the power of maturation can no longer be recalled? My apparatus for enclosing fruits in a vacuum was the following:-I first put them into a jar, and closed it with a good cork, covered carefully with resinous cement, and having a very small hole bored through its centre with a red-hot knitting needle. This being done, I put the jar on the air-pump plate, whelmed over it a glass receiver, fitted with a copper stem, which could be raised or sunk through an air-tight leather collar. When a vacuum was made in both jars, I pressed down upon the hole of the cork of the inner jar, the copper stem, which carried a small plug of wax at its extremity, and thus the cork was made air-tight by the wax-plug that was left in the hole. To fill the jar with carbonic acid or hydrogen gas, two holes were made in the cork, to receive two bent glass tubes, one

proceeding from the vessel in which the materials for furnishing the gas were put, and the other dipping under water or mercury; a current of the required gas was then passed through the jar, till it was presumed that all the atmospheric air was displaced. To fill it with azotic gas, the bottom of the jar was covered with a stratum of moistened protoxyd of iron, recently prepared, and the fruit was then put in on a small partition of tinplate, and the jar sealed up; and thus the air of the jar was left to be deprived of its oxygen by the action of the protoxyd of iron, leaving its azote untouched."-An. de Chimie.

Nen Zealand Spinach. Though known to botanists, says Mr. Anderson, for many years, and notwithstanding its value as an esculent had been ascertained by the first discoverers of the plant, the tetragonia expansa till only within these few years has been cultivated as a matter of curiosity.

Our first knowledge of this plant was derived from sir Joseph Banks, who discovered it in the beginning of the year 1770, at Queen Charlotte's Sound, in New Zealand, when with captain Cook in his first voyage round the world. In the account of that voyage, edited by Dr. Hawkesworth, it is mentioned amongst the plants of New Zealand as having been met with once or twice, and resembling the plant called, by country people, lamb's quarters, or fat-hen; it was boiled and eaten instead of greens." Specimens and seeds were brought to England, and its introduction by sir Joseph Banks to Kew-gardens is recorded to have taken place in 1772. The value of the plant became more known in captain Cook's second voyage. Forster, who went

with that expedition, found it also at Queen Charlotte's Sound in great abundance in 1773; and during the stay of the ships at that place, the sailors were daily supplied with it at their meals. Thunberg found it growing wild in Japan, where it is called tsura na, or creeping cabbage. Besides the works above mentioned, it has also been described and figured by Scopoli, by Roth, and by M. de Candolle. Several of the writers, which I have referred to, note the plant as biennial, but in our climate it certainly is only an annual. From the experience which I have had in the cultivation of the tetragonia, in the present year, I can venture to recommend the following treatment; the seed should be sown in the latter end of March in a pot, which must be placed in a melon frame; the seedling plants, while small, should be set out singly in small pots, and kept under the shelter of a cold frame, until about the twentieth of May, when the mildness of the season will probably allow of their being planted out, without risk of being killed by frost. At that time a bed must be prepared for the reception of the plants, by forming a trench two feet wide, and one foot deep, which must be filled level to the surface with rotten dung from an old cucumber bed; the dung must be covered with six inches of garden mould, thus creating an elevated ridge in the middle of the bed, the sides of which must extend three feet from the centre. The plants must be put out three feet apart; I planted mine at only two feet distance from each other, but they were too near. In five or six weeks from the planting, their branches will have grown sufficiently to allow the gathering

of the leaves for use. In dry seasons, the plants will probably require a good supply of water. They put forth their branches vigorously as soon as they have taken to the ground, and extend before the end of the season three feet on each side from the centre of the bed. The branches are round, numerous, succulent, palegreen, thick, and strong, somewhat procumbent, but elevating their terminations. The leaves are fleshy, growing alternately at small distances from each other, on shortish petioles; they are of a deltoid shape, but rather elongated, being from two to three inches broad at the top, and from three to four inches long; the apex is almost sharp-pointed, and the two extremities of the base are bluntly rounded; the whole leaf is smooth, with entire edges dark green above, below paler, and thickly studded with aqueous tubercles; the midrib and veins project conspicuously on the under surface. The flowers are sessile in the ale of the leaves, small and green, and, except that they shew their yellow antheræ when they expand, they are very inconspicuous. The fruit when ripe has a dry pericarp of a rude shape, with four or five hornlike processes inclosing the seed, which is to be seen in its covering. In gathering for use, the young leaves must be pinched off the branches, taking care to leave the

leading shoot uninjured; this, with the smaller branches which subse quently arise from the ale of the leaves which have been gathered, will produce a supply until a late period in the year, for the plants are sufficiently hardy to withstand the frosts which kill nasturtiums, potatoes, and such tender vegeta bles. The tetragonia is dressed exactly in the same manner as spinach, and whether boiled plain or stewed, is considered by many superior to it; there is a softness and mildness in its taste, added to its flavour, which resembles that of spinach, in which it has an sdvantage over that herb. My whole crop in the present year consisted solely of nine plants, and from these I have been enabled to send in a gathering for the kitchen every other day since the middle of June, so that I considers bed with about twenty plants quite sufficient to give a daily supply, if required for a large table. The great advantage of this vegetable is as s substitute for summer spinach. Every gardener knows the plague that attends the frequent sowing of spinach through the warm sea son of the year; without that trouble, it is impossible to have it good, and with the utmost care it cannot always be even so obtained exactly as it ought to be (particu larly when the weather is hot and dry), from the rapidity with which the young plants run to seed.

Instrument for finding the latitude, at once, without the help of logarithms or calculation, from two observations taken at any time of

day. The inventor of this instru ment, Joseph Bordwine, esq. pro fessor of fortification at the East India Company's military college