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XXIV. On a Remarkable Structural Appearance in Phosphonts. 

 By Charles Tomlinson, F.R.S., F.C.S* 



THE following remarkable appearance in phosphorus was 

 described to me some months ago by Mr. James John 

 Field, F.C.S., who requested me, if possible, to account for it. 



About four years ago Mr. Field placed half a dozen sticks 

 of phosphorus in a cylindrical jar containing water which rose 

 about half an inch above the ends of the sticks, and the jar 

 was closed with a bung. This jar was placed in a cellar, where 

 it remained undisturbed for about three years. The cellar is 

 ilagged with stone, is surrounded by damp walls, and almost en- 

 tirely protected from light and currents of air. The maximum 

 temperature probably does not exceed 50° or 55° F. 



After this long repose the jar was taken into the laboratory, 

 when it was found that the level of the water had sunk to about 

 one-third of its original height, and the liquid left in the jar had 

 become as dense and thick as the strongest syrup ; it consisted 

 of a solution of PO 3 and PO 5 . 



The portions of phosphorus that rose some inches above the 

 liquid, instead of being cylindrical as before, were conical from 

 a sharp point to the full diameter, and each cone had a double 

 spiral running down it from left to right, as if two flat tapering 

 bands of the substance had been made to cohere at right angles 

 lengthwise, and then twisted into a pointed rod — or just as if 

 the sticks had been mounted in a screw-cutting lathe, geared to 

 cut a coarse tapering double spiral. The sticks had also changed 

 from the creamy opaque surface to a translucent barley-sugar 

 appearance from the surface of the liquid up to the points. 



In attempting to explain the appearances described, we must 

 consider, first, the wasting away of the sticks and their conical 

 form, and, secondly, the twisted structure. 



First. The wasting away of the sticks and their conical form 

 are clearly effects of slow combustion, diminishing in intensity 

 downwards. The continued combustion and also the evapora- 

 tion of the water must have been clue to a badly fitting cork 

 which, during a falling barometer, allowed a portion of the moist 

 air to escape from the jar, and during a rising barometer allowed 

 a portion of comparatively dry air to stream in. Had the jar 

 been subject to considerable variations in atmospheric tempera- 

 ture, the effects would have been more rapid ; but as the tempera- 

 ture of the cellar was pretty constant, there is nothing to detain 

 us here. Going back, then, to variations in atmospheric pres- 

 sure, the level of the -water in the jar would be gradually lowered 



* Communicated by the Author, having been read at the British Asso- 

 ciation at Exeter, August 19, 1869. 



