Purday, whose reputation as a rifle maker is deservedly high, has brought them to great perfection; and some beautiful guns of this description may be seen at his manufactory, which, though so small in the gage as to require bullets eighty to the pound, are perfect alike in execution and workmanship. With respect to the _Air-cane_, though a more recent invention, it is only necessary to say, that it has all the disadvantages of the air-gun, with much weaker power, and a greater liability to get out of order. It is a mere toy, and, certainly, a very dangerous one. * * * * * Formerly, poachers were in the habit of using air-guns to destroy pheasants in the preserves. The instrument made no noise, and the operator preferred the boisterous, rainy night, when the moon was nearly at the full; the wet did not in the least affect the discharge of this implement, and the keepers knew a common gun could not be effectually employed in such tempestuous weather; besides, the report caused immediate alarm, and frequent detection. Vast numbers of pheasants were carried off, before this practice was discovered. The late Mr. Tyssen was partial to an air-gun for shooting rooks, rabbits, &c., and was using one at Donyland Park, in Essex, when the screw of the valve gave way, as the servant was pumping the air into it; the copper ball fortunately took such a direction, that no one was hurt; but, in passing through the trees, it cut off some considerable branches. This accident staggered his confidence in the security of their principle, and from the best informed persons he consulted upon the subject, he was convinced there was no certainty of their being safe, and he wisely relinquished the air-gun, with all its asserted superlative properties.—_Daniel._ AIRY, _a._ Composed of air; relating to the air; high in air; light as air; gay, sprightly, full of mirth, lively. ALCOHOL, _s._ A highly rectified spirit of wine. ALKALI, _s._ Any substance which combines with an acid, and produces a salt. _Alkalies_ form one of the classes of saline bodies, and are of three kinds: the _vegetable alkali_—kali, or potash,—the _mineral alkali_—soda, or natron,—and the _volatile alkali_, or ammonia. _Alkalies_ are distinguished by their changing blue vegetable colours to a green, and yellow to orange; by combining rapidly with acids, and forming with them neutral salts—and by rendering oils miscible with water. _Vegetable_ and _mineral alkalies_, not being evaporable, except in a high degree of heat, are termed _fixed_: and _ammonia_, being evaporable in a low temperature, obtains the name of _volatile alkali_.—_White._ ALKALINE, _a._ That which has the qualities of alkali.