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The Surinam toad, represented in No. 8, is also the possessor of one of the strangest nurseries known to science. It lives in the dense tropical forests of Guiana and Brazil, and is a true water-haunter. But at the breeding season the female undergoes a curious change of integument. The skin on her back grows pulpy, soft, and jelly-like. She lays her eggs in the water: but as soon as she has laid them, her lord and master plasters them on to her impressionable back with his feet, so as to secure them from all assaults of enemies. Every egg is pressed separately into a bed of the soft skin, which soon closes over it automatically, thus burying each in a little cell or niche, where it undergoes its further development. The tadpoles pass through their larval stage within the cell, and then hop out, in the four-legged condition. As soon as they have gone off to shift for themselves, the mother toad finds herself with a ragged and honeycombed skin, which must be very uncomfortable. So she rubs the remnant of it off against stones or the bark of trees, and re-develops a similar back afresh at the next breeding season.

"Sir Humphry Davy?" said Mr. Brooke, over the soup, in his easy smiling way, taking up Sir James Chettam's remark that he was studying Davy's Agricultural Chemistry. "Well, now, Sir Humphry Davy; I dined with him years ago at Cartwright's, and Wordsworth was there too--the poet Wordsworth, you know. Now there was something singular. I was at Cambridge when Wordsworth was there, and I never met him--and I dined with him twenty years afterwards at Cartwright's. There's an oddity in things, now. But Davy was there: he was a poet too. Or, as I may say, Wordsworth was poet one, and Davy was poet two. That was true in every sense, you know."

A scorifier is essentially a roasting dish sufficiently thick to resist, for a time, the corrosive action of the fused metallic oxides it is to contain. The essential property of a cupel is, that it is sufficiently porous to allow the fused oxide to drain into it as fast as it is formed. It should be large enough to absorb the whole of the liquid; and of course must be made of a material upon which the liquid has no corrosive action. Cupels do not bear transport well; hence the assayer generally has to make them, or to supervise their making. A quantity of bone ash is carefully mixed with water so that no lumps are formed, and the mixture is then worked up by rubbing between the hands. The bone ash is sufficiently wet when its cohesion is such that it can be pressed into a lump, and yet be easily crumbled into powder. Cupel moulds should be purchased. They are generally made of turned iron or brass. They consist of three parts (1) a hollow cylinder; (2) a disc of metal; and (3) a piston for compressing the bone ash and shaping the top of the cupel. The disc forms a false bottom for the cylinder. This is put in its place, and the cylinder filled (or nearly so) with the moistened bone ash. The bone ash is then pressed into shape with the piston, and the cupel finished with the help of three or four smart blows from a mallet. Before removing the piston, turn it half-way round upon its axis so as to loosen and smooth the face of the cupel. The cupel is got out by pressing up the disc of metal forming the false bottom; the removal is more easily effected if the mould is somewhat conical, instead of cylindrical, in form. The cupels are put in a warm place to dry for two or three days. A conveniently sized cupel is 1-1/4 inches in diameter and about 3/4 inch high. The cavity of the cupel is about 1/4 inch deep, and something of the shape shown in fig. 5.

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