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LIFE OF COLONEL MACERONI.

seen abundant instances of their saving qualities. Butthe most secure way of applying them in such a case as thepresent, is to have them isolated near, hut not upon, themagazines. For such conductors to be of sure avail, theymust be of a competent diameter, or mass of metal: thosegenerally used are not a quarter big enough. The smallestpart should he an inch in diameter, and be it borne in mindthat a tube, having two surfaces, has twice the conducting-power of a solid bar. Copper or zinc is far better than iron, inas much as they are less liable to oxydation. The upper ex-tremities should be strongly gilt or rather plated with goldor platinum. I say “ extremities,” because it is very advan-tageous for it to terminate in several branching points.If to preserve a metallic conductor from rust, it be coatedwith paint, or pitch, or tar, its saving qualities are notmerely impaired, but it invites the danger it was meant toparry. The electric discharge is drawn to the gilded or copperextremity; but, instead of being conducted down the roduntil it becomes dispersed in the water or the ground, it isapt to fly off the pitched or painted surface in the midst ofits course, and so injure the building instead of protecting it.By and by, when I shall again have occasion to speak ofRome, under the French dominion in 1812, I shall say a fewwords more on lightning conductors, of which the French made a very salutary application to St. Peter’s church andother edifices.

It was in 1810 that I made some experiments in trans-planting hair from one person’s head to another. I trans-ferred several of Tom Williams’s light-coloured hairs on tomy own skull, where they grew, and are thriving still; viceversa I planted several of my own black hairs to the headof Williams, on which they still flourish, and preserve theirprimitive hue, The way I did it was, to prick a hole in