VOL. XLIII.] PHILOSOPHICAL TRANSACTIONS. /5 



tended : he took hold with one hand of the rusty iron tube, and held the fingers 

 of the other over some of the quinta essentia; and the sparks from his fingers im- 

 mediately struck with such violence into the silver spoon that held it, that the 

 essence was in a moment set all in a flame. 



This experiment, so unexpected, gave the greatest satisfaction to all the com- 

 pany; and an account of it was published in the Leipsic Gazette of the 21st of 

 May; where it was also mentioned, that divers other experiments, with the sparks 

 of electrified metal, had already been made both at Dantzic, and at Berlin. 



Dead fowls, pork, and veal, both raw and drest, may be made electric by a tin 

 tube, or by the hand of man; insomuch that the sparks, proceeding from those 

 several bodies, will also kindle the same essence. 



If such fluid bodies, as are usually kindled by flame, are not fine enough, they 

 need only be warmed a little in the spoon : or the spirits may be lighted a little be- 

 fore, and blown out again, before they are brought to the electrical body. In this 

 manner he kindled, with the electrical sparks, camphorated spirits of wine, 

 coloured with saiFron ; the common essentia vegetabilis ; and even French brandy, 

 and corn-spirits, only taking the precaution of warming these liquors a little be- 

 fore. Even oil, pitch, and sealing-wax, may be lighted by the electric sparks, 

 provided they are before heated to a degree that is next to kindling. 



Observations on several newly discovered Species of Fresh-water Polypi. By 

 M. Abraham Trembley, F. R. S. N°474, p. 169. 



We find, in divers places, on water-plants, and other bodies in the water, a 

 whitish substance, that looks at first only like a sort of mould : we sometimes see 

 plants, sticks of wood, snail-shells, and the like, that are entirely covered over 

 with this substance. But if we take any of these, put them into a glass of clear 

 water, and then examine with a magnifying glass what is upon them, we soon 

 discover in the little bodies which by their assemblage, form this whitish sub- 

 stance, such motions as give sufficient reason to consider them as living ani- 

 mals; and this will appear yet more sensible, when they come to be observed 

 with a microscope. We then find them to be minute bodies, severally fixed to 

 the extremities of small stems, or pedicles, many of which are often so united, as 

 to form together a sort of branches, or clusters; and this appearance determined 

 Mons. De Reaumur to name the animalcula that appeared so fixed, clustering 

 polypi ; des polypes en bouquet. These clusters are larger or smaller, according 

 to the species of the polypi that form them, and to the concurrence of many 

 other circumstances. 



To get a clear idea of the figure of these animals, it is best to observe the 

 smaller clusters ; as, in the larger, the great number of the polypi on the several 

 stems, are apt to hide each other. 



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