A Gardener's Barometer

Tho common caniphor-bottlo makes a very oloudy index of atrnospheric woight and weather changes on which tho iollowing ia an improveinent. Dissolve two and one-half drachms of caniphor in eleven fluid drachms of alcohol, Put thirty eight grains of nitrato of potash (saltpetre), and thirty-eight grains of muríate o: ammonia (sal ammoniac), into nino fluic drachms of water ; when all are perfectly dissolved, mix the two solutions. Shake them well in a two-ounce or four-ounce white vial, cork very loosély, or, botter, tie over the mouth a piece of linen or cotton cloth, and placo the instrument in a good light out of the suushine, where it oan be observed without handling. When tho weathor is fine and clear, tho fluid is also ; but on the least change, the chemicals, whicn lie as a sediment, rise in boautiful frondliko crystalsproportionately, and again duly subsido. By watching these changes one soon becomes ablo to predict tho changes prabable for a few hours to come in any locality. This instrument is also a pretty philosophica' toy, showing how sensitive somechemica! solutions are to atmospheric influences. - We saw barometers of this kind for sale in London, several years ago, but do nol recollect meeting with them in this country, except the home-made ones prepnrec Hccording to the above directions, which have been several times published, bui