Intelligence and Miscellaneous Articles. 317 



plants, and at night it kills them in very small quantity ; but in the 

 daytime they do not appear to be sensibly altered, although the 

 disengagement of gas is abundant. 



Sulphuretted hydrogen. — The results of the experiments with this 

 gas were precisely similar to those of the last. The plants left during 

 the night in the same mixture of gases which did not at all injure 

 them in the light, were quite withered in the morning, and the gas 

 was absorbed. Cabbage onl}' resisted. 



Muriatic acid gas. — The results were similar to the last. The 

 plants did not perish in the daytime, even when there was gas 

 enough to render one or two leaves brown : they were completely 

 dead in the morning, leaving the peculiar smell already mentioned. 

 Cabbage was still an exception. 



It appears, then, from these experiments, that several gases are 

 hurtful to vegetation, but that their action occurs only during the 

 absence of light, as M. De Candolle had foreseen. — Annates des 

 Sciences Naturelles, April 1833. 



LEDEREH1TE, A NEW MINERAL. 



This substance was found by Dr. Jackson and Mr. Alger at Cape 

 Blomidon, in Nova Scotia, beneath a precipice of basaltic rocks, 

 from which it had recently fallen, with a large vein of stilbite, me- 

 sotype and analcime. The crystals are generally implanted in anal- 

 cime or stilbite ; some are colourless, transparent and extremely 

 brilliant; others are of a salmon red colour, and translucent only : 

 the colour being irregularly disseminated, it is evidently accidental. 

 Its hardness is nearly the same as that of felspar, which it scratches 

 with difficulty, being itself powdered by the friction. Specific gra- 

 vity 2-169. The crystals have generally the form of low, six-sided 

 prisms, terminated at each extremity by six-sided pyramids, which 

 are replaced at their summits by little hexahedral tables. Some of 

 the crystals have transverse stride, which were at first supposed to 

 indicate a rhomboid as the primary form ; but the plane termina- 

 tions indicate a six-sided prism, which, from the direction of the na- 

 tural joints, made visible by heating the crystal, seems to be its pri- 

 mary form : no nucleus could, however, be obtained by cleavage. 

 This mineral, named Ledererite, in honour of M. Lederer, Austrian 

 Ambassador to the United States, yielded by analysis, 



Silica 49-47 



Alumina 21 '48 



Lime 11-48 



Soda 3-94 



Phosphoric acid .... 3-48 



Oxide of iron 14 



Water 8-58 



Foreign matter .... '03 



Loss 1-40 



100-00 

 Sill/ man's Journal, October 1833. 



