552 Intelligence and Miscellaneous Articles » 



K+L+B-fV, is subject to some uncertainty, arising from the cir- 

 cumstance that the platinum, of which A, B, C, F were made, had 

 been very badly prepared and contained cavities filled with some 

 hygroscopic substance which rendered the weight of B slightly 

 variable, according to the greater or less amount of moisture present 

 in the atmosphere. According to these observations, the kilogramme 

 des Archives =15432'3481G grains. 



By the observations of Schumacher and Steinheil on the ratio of 

 the weight of ^ to that of Sp, subject to tai uncertainty of 0*00139 

 grain, on account of an error of the press, and the comparison of Sp 

 with PS, the weight of ^ is either 15432-34873 or 15432-35012 

 grains, of which PS contains 7000. 



The French standard of commercial weight is a brass kilogramme 

 H, known as the kilogramme type laiton. It is deposited at the 

 Ministere de I'lnterieure. According to a comparison of H with ^, 

 the result of which is published in the 25th volume of the Modena 

 Transactions, the apparent weight of H, when weighed in air at 

 Somerset House, the mercury in the barometer, reduced to the free- 

 zing-point, standing at 29' 75 inches, and the thermometer at 65-66 F, 

 (i=755-64mm., ^=18-7 C), is 15432-344 grains, of which the 

 English commercial standard contains 7000. 



LXXI. Intelligence and Miscellaneous Articles. 



NOTE ON THE NEW ZEOLITE FROM SKYE, ANALYSED BY MALLET. 

 BY DR. HEDDLE. 



n^HE mineral analysed by Mallet (Silliman's American Journal, 

 ■*- Sept. 1856, p. 179) is Laumonite, somewhat effloresced from 

 having been " several years " in his possession. An analysis of a 

 similar specimen was published by Scott (Jameson's Journal, October 

 1852, vol. liii. p. 284), which specimen also bore the name hypo- 

 stilbite, and I have seen many other specimens in cabinets in this 

 country with the same name attached. As it bears but very slight 

 resemblance to the substance called hypostilbite by Beudant, the 

 christening may be explained by the ignorance of some unprincipled 

 dealer resorting to a rare title in order to rid himself of a superabun- 

 dance of an insignificant-looking substance. It occurs in a vein at 

 the Storr in Skye, in immense quantity ; the vein has an average 

 thickness of about \\ inch, and the appearance is exactly as de- 

 scribed, — " a mass of minute crystals resembling loaf-sugar, breaking 

 easily, and crumbling under the fingers into a coarsish crystalline 

 powder." The external characters of hardness, gravity, transparency, 

 &c.,as given, agree with those of Laumonite ; — the latter has a pearly 

 lustre on cleavage planes, and is raonoclinic ; gelatinizes, which stil- 

 bitic minerals do not do ; and the fact that minute crystals of stilbite 

 do occur in small cavities of the substance, may explain the -87 of 

 potash with some soda. Being Laumonite, the several years have 

 told upon the proportion of water, but in other respects the analysis 

 agrees with those of Laumonite, especially with that of Scott ; and 

 it may be observed that those by Connell and Babo, of Skye speci- 



