124 M. Ulex on Struvite. 



4. According to my experiments, chemical and voltaic ozone 

 are instantaneously destroyed by a number of gaseous sub- 

 stances, ex. gr. by defiant gas, sulphurous acid, fumes of 

 hyponitric acid, vapour of aether, &c. Hence it conies that 

 phosphorus placed in atmospheric air, mixed with small 

 quantities only of any of the substances named, does not pro- 

 duce ozone, and it is well known that phosphorus remains 

 dark under the same circumstances. If the experiment be 

 made as indicated under § 3, the electrical brush, lively as it 

 may happen to play within the air of the bottle, does not call 

 forth in phosphorus the slightest sign of phosphorescence, 

 provided the atmospheric air surrounding phosphorus contain 

 some defiant gas, hyponitric acid, &c. 



5. Some time ago I ascertained the fact that either platinum 

 black or spongy platinum has the power of destroying indigo, 

 of colouring blue the resin of guaiacum, of decomposing iodide 

 of potassium, in short, of producing oxidizing effects very 

 similar to those brought about by the electrical brush or spark. 

 That similarity of action made me suspect that, with regard to 

 phosphorus, platinum being in a state of minute mechanical 

 division, might conduct itself like electricity, and the results 

 of my experiments have proved the correctness of my conjec- 

 ture. At a temperature of 4° R. below zero, newly-prepared 

 platinum black was placed upon a watch-glass ; now, as soon 

 as a piece of phosphorus (having previously been wiped 

 with filtering-paper) was made to touch the metallic powder 

 it became luminous, first at the point of contact, and imme- 

 diately afterwards along its whole surface. On breaking that 

 contact, the phosphorus turned dark again. 



6. Spongy silver, as it is obtained from the acetate of that 

 metal, acts upon phosphorus as powerfully as spongy platinum 

 does; for no sooner has phosphorus been touched by the 

 silver than the former becomes luminous, even at a tempera- 

 ture of 6° R. below zero. 



7. Iron, lead, copper, antimony, bismuth, tin, in a state of 

 minute mechanical division, have no effect upon phosphorus. 

 With gold, iridium, and the rest of the metals, I have not 

 yet made any experiment. 



XXIV. On Struvite, a new Mineral. By G. L. Ulex*. 



NUMEROUS crystals were found in digging out the 

 ground of St. Nicholas church, in the middle of our 

 town ; the largest of which are about one inch long, and weigh 



* Communicated by the Chemical Society; having been read March 2, 

 1846. 



