1. The herein described process of manufacturing phosphorescent materials, which consists in heating sea shells red-hot, treating them while heated with a bath of brine, then, after removal from the bath, mixing sulphur and phosphide and sulphide of calcium therewith, and finally subjecting the mixture to a white heat, substantially as and for the purpose described.
2. The described process, which consists in placing clean and red-hot clam shells in a saturated solution of sea salt, and then drying them, for the purpose specified.
BOXWOOD AND ITS SUBSTITUTES.
[Footnote: Prize essay written for the International Forestry Exhibition, Edinburgh.]
By JOHN R. JACKSON. A.L.S., Curator of the Museums, Royal Gardens, Ken.
The importance of the discovery of a hard, compact, and even grained wood, having all the characteristics of boxwood, and for which it would form an efficient substitute, cannot be overestimated; and if such a discovery should be one of the results of the present Forestry Exhibition, one of its aims will have been fulfilled.
For several years past the gradual diminution in the supplies of boxwood, and the deterioration in its quality, have occupied the attention of hardwood merchants, of engravers, and of scientific men.
Of merchants, because of the difficulties in obtaining supplies to meet the ever increasing demand; of engravers, because of the higher prices asked for the wood, and the difficulty of securing wood of good size and firm texture, so that the artistic excellence of the engraving might be maintained; and of the man of science, who was specially interested in the preservation of the indigenous boxwood forests, and in the utilization of other woods, natives, it might be, of far distant countries, whose adaptation would open not only a new source of revenue, but would also be the means of relieving the strain upon existing boxwood forests.