21 



If the face or hands be smeared with this, they will 

 shine in the dark, yet without any hurt to the skin. 



If phosphorus be put into a long phial, of which three 

 fourths are tilled with water, it will frequently send up 

 confiscations, which will pierce through the water, and 

 expand themselves with great brightness in the upper part 

 of the phial. 



If we compare this with lightning, we may observe, 

 that as in this the fire passes alternately through the wa- 

 ter, so in that the flashes, which come at intervals, pass 

 uninterupted through the most dense clouds and thickest 

 rain. But this is usually in warm weather, not in winter. 

 And it is the same with phosphorus. It very frequently 

 flashes in warm weather, but very rarely in winter. 



Again, The flame of lightning is generally inoffen- 

 sive, and does not set fire to any thing. In like man- 

 ner the flashes of phosphorus are harmless, and do not set 

 fire to the most combustible matter. But when con- 

 densed phosphorus is set on fire, it burns terribly. And 

 in the same manner lightning, when condensed, burns 

 trees, houses, or whatever it comes near. Phosphorus 

 while burning, acts as a corrosive, and* when it goes out, 

 forms a menstruum, which dissolves gold, iron, and 

 other metals. Lightning melts the same substances. 



Another kind of artificial phosphorus, is a preparation 

 of the bononian stone. This stone is of no certain 

 figure, but is sometimes round, sometimes oblong, or 

 lenticular. They are usually as big as an orange, but 

 very light, considering their bulk. They are of various 

 colours, some ash-coloured, some blue, and some almost 

 white. When this stone is prepared, it receives light, 

 but in very different degrees, either from the sun, the 

 moon, common day-light, or a flame. After it has been 

 exposed a few minutes to any of these, it shines in the 

 dark like a burning coal, with such a light as is suffi- 

 cient to read by, if the letters be held near the stone. 

 It does not retain its light long, but requires often re- 

 newing. When well prepared, it will retain this virtue 



