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winter gales, they stood all but that which occurred the begining of this month; it moved them, and they were found lying on the north slope. There were three of them, one of nine tons and the other two of five tons each ; they are to be replaced for further trial.

2. Moveuble Axletree. Mr. Ackermann of the Strand has lately introduced a considerable alteration into the axletree of carriages. The improvement, it is said, will allow the carriage to be built 18 inches shurter ; the body to be hung lower, and the fore wheels to be made larger. The vehicle will turn in much less space than carriages of the common construction, and is more difficult to overset. Several coachmakers are constructing carriages upon this new plan.

3. New Harpoun. A new harpoon has been invented by Mr. Robert Garbutt, of Kingston upon Hull, for the Greeland fishery ; calculated to secure the whale in the event of the shank of the instrument breaking. The improvement consists in placing a kind of preventer made fast to the eye of the foregager, which passing along the shank of the harpoon, is attached to the thick part of it in such a manner as neither to lessen its strength nor impede its entrance when the fish is struck.

4. Harpoon Guns. Some of the Leith whale ships are furnished with harpoon guns for this year's service. The gun is mounted on the bow of the boat, and the harpoon with the line attached is fired out of it, and will strike at the point blank distance of 20 or 30 fathoms; by which means a fish may be struck when there is no chance of reaching it by throwing the dart with the hand. They have been used by the Hull vessels for several years.

5. Nautical Instrument. Among other ingenious inventions submitted to the Board of Longitude, one countenanced by the Board and recommended to the Lords of the Admiratly for immediate trial, is likely to facilitate the object intended in exploring the polar regions. The merit of this invention is, that it works horizontally and

vertically, assuming the magnetic meridian by its own action. The inventor is Mr. Lockwood of the navy.

6. Machine to Sweep Chimnies. Mr. C. Carr, of Paddington, has constructed a machine to sweep chimnies, which appears to possess great advantages. It is complete of itself, requiring no chain, pulley, or other appendage in the chimney, and will sweep very clean as well in horizontal as perpendicular flues. If the flue be angular, having one or more bends, the person who uses it can ascer. tain the direction in which the angle goes off, and can turn the head of the instrument the proper way. There is a means also of ascertaining when the head of the instrument has reached the top of the chimney, so that no danger of thrusting off the iron smoke cowls is incurred. It works in a very cleanly manner entirely from below, and can casily be made fire proof when necessary.

7. Prevention of the Dry Rot. Mr. John Shilliber, of Walkhampton near Plymouth, proposes to prevent the dry rot in timber, by cutting it down when all vegetation has entirely ceased, as at Christmas, instead of felling it inimediately after the tree has recommenced its growing

In the last case it is said the pores are open and extended, the wood soft, the bark separates with ease, and when the juices of the tree have dried up, the pores remaining open, allow the wood to become infected with the disease. In the former the pores are considered as naturally closed, the sap and other easily changing fluids have descended into the root, or formed more solid matter, the bark adheres very closely and firmly to the wood, and the wood is much harder and more impenetrable, and is not affected by the dry rot. These conclusions have been drawn from a comparison of timber fellcd at different periods,

II. CHEMICAL SCIENCE.

§ I. CHEMISTRY.

1. Alkali from Potatoe Stalks. The attention of the people of Ireland has been called to the extraction of potash from potatoe stalks. Processes for that purpose have been commenced, and they promise to produce in that part of the British dominions a most important article of trade. It is calculated that 350,000 acres of land are annually cultivated with potatoes; these would produce 46.875 tons of potash, whieh, at £20. per ton, would amount to £937.500. per annum.

2. Tungstic Acid. M. Chevreul has observed, that by heating the tungstate of ammonia with tincture of turnsole, the acid properties of the tungstic combination are rendered evident by the change of colour.

3. Copper dissolved in Hydrogen. Hydrogen gas (says M. Lampadius) dissolves copper when it is passed over this metal in fine powder at a white heat. The gas then burns with a green flame, and forms, during its combustion, an oxide of copper.

4. Homberg's Pyrophorus. Homberg's pyrophorus is said to be more certain in its preparation, when it of sulphate of soda is added to the mixed alum and flour.

5. Test for Sugar. It has been proposed by M. Doberenier, to test sugar in solution, in small quantities, by adding to a portion of the liquid, a few grains of yeast, and placing it in a vessel closed by mercury. A ferınentation takes places, and the bulk of gas liberated indicates the quantity of sugar.

6. Temperature on and beneath the Surface of the Earth. The mean temperature of Paris, deduced from many years observation, is 10° 6' of the centigrade scale, = 51° Fahrenheit. The temperature of the caves beneath the Observatory have been for a long time 11°71' = 540 Fahrenheit. What is the cause of this difference of inore than 1° between two results, = 3° Fahrenheit, which, according to theory, should correspond?

7. Uranium. It has been ascertained by M. Chevreul that the peroxide of uranium is soluble in the alkaline sub-carbonates, and forms, with that of potash, a regularly crystallized salt. No carbonic acid is disengaged. The solution is of a fine yellow colour, similar to that of the chromate of potash.

8. Chromic Oxide and Acid. Chromic oxide heated with alkali becomes chromic acid, and chronic acid heated with an acid becomes chromic oxide; the oxide in solution is green, and the acid yellow, and the change of state and colour may be produced successively at pleasure.

9. Cocoa Nut Oil. Cocoa nut oil is perhaps the most volatile of what are called the fixed oils ; when heated, it distils over with scarcely any decoinposition, and the part distilled, when washed, is similar to the original oil.

10. Wire Gauze Safety Lamp. To shew how far the security afforded by means of wire gauze might be applied to the procuring light in the mines, Sir H. Davy has lately made an Argand's lamp safe by means of it. It required no glass, the cylinder of gauze supplying its place. It, as was expected, answered perfectly.

11. Snake Stones. Dr. Davy has lately analysed the snake stones of India. He found them to be of three kinds ; one was merely calcined bone; another carbonate of lime, coloured by a vegetable substance; and the third a bezoar stone. The idea entertained by the natives, of their power over the bite of poisonous snakes, is entirely unfounded.

12. Strength of Ale. Ale brewed by Sir Joseph Banks, being analysed at his desire by Mr. Brande, gave the following proportion of alcohol.

1. Malt to the hogshead 8 strike.* Hops to the hogshead 8 lbs. Brewed 11th January, 1816_contained 9.85 per cent. of alcohol.

2. Malt to the hogshead 10 strike. Hops to the hogshead 11 lbs. Brewed 27th February, 1815—contained 10.84 per cent. of alcohol.

* By strike is meant a busbel measure of inalt, not heaped up but struck off to a level with the rim.

13. Change of Colour by Acids. The effects of muriatic acid gas and ammoniacal gas upon turmeric paper, are so similar, that it is difficult to distinguish the two by this test alone. The acid reddens it almost as much as the alkali. Phosphoric, nitric, muriatic, and particularly sulphuric acid, also redden turmeric paper; but in all these cases, water, even in small quantities, immediately restores the original colour.

14. Yellow Dye. A chemist of Copenhagen is said to have discovered a brilliant yellow matter for dying, in potatoe tops. The mode of obtaining it, is by cutting the top when in flower, and bruising and pressing it to extract the juice. Linen or woollen soaked in this liquor during 48 hours, takes a fine solid and permanent yellow dye. If the cloth be afterwards plunged in a blue dye, it then acquires a beautiful permanent green colour.

15. Analysis of Sweet Almonds. M. Boullay has given an analysis of sweet almonds as follows.Oil,

54 Albumen,

24
Sugar (fluid)

6
Fibre,
Gum,

3
Pellicles,

5 Water,

3.5 Acetic acid and loss, 5

[blocks in formation]

16. Cholesteric Acid. MM. Pelletier and Caventon have obtained a new acid from cholesterine or the pearly substance of human biliary calculi discovered by Poulletier-de-Laselle, and named by Chevreul. Cholesterine is to be heated with its weight of strong nitric acid until it ceases to give off nitrous gas. A yellow substance separates on cooling, scarcely soluble in water, and which, when well washed, is pure cholesteric acid.

It is soluble in alcohol, and may be crystallized by evaporation. It is decomposed by a heat above that of boiling water,

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