Lieut. Baddeley on Sulphate of Stt^ontian, ^<. 105 



recently, on this and other topics, given substantial proofs of their 

 industry and zeal, in the first volume of the Transactions of the 

 Literary and Historical Society of Quebec, of which Lieut. Baddeley, 

 the author of the following paper, appears to be an efficient member. 

 In a letter accompanying the present communication, he mentions 

 the importance of observing and registering facts in natural history, 

 although (with how little necessity will be apparent on reading his 

 paper) he disclaims the character of an adept, or, to use his own 

 word, of being one of the initiated. 



Sulphate of Strontian, ^c. 



Color, milk and water white ; translucent ; structure, fibrously 

 laminar ; the mineral being composed of long bladed laminae, aggre- 

 gated together : these laminae often appear to radiate from a centre, 

 and diverge like the sticks of a fan ; sometimes they are interlaced. 

 The lustre on the faces of the laminae is pearly and shining, and 

 points of iridescence occasionally appear. It breaks easily, particu- 

 larly in the direction of the fibres, into fragments which are long 

 rather than broad, and often wedge-shaped ; these are further easily 

 reduced to white powder, rather soft to the touch, and slightly gritty 

 to the taste. Its hardness is very little greater than that of some 

 calc-spars, while it is less than that of many ; the magnesian varie- 

 ties for instance, with which (judging from their pearly lustre and 

 often curvedly laminar structure) it is frequently associated. Its sp. 

 gr. lies between 3.9 and 4.1. Cold diluted muriatic acid produces 

 apparently no effect upon it, with the exception that a few bub- 

 bles of gas sometimes escape with effervescence : a change however 

 has evidently taken place, because, if a small piece of stick be inserted 

 into the powder of this mineral, which has been previously moistened 

 with the acid, and if the stick* be afterwards drawn over the wick of 



markable in the case of sulphate of barytas, and feeble in the sister mineral. 

 The sp. gr. stated by Lieut. Baddeley, is in favor of the sulphate of strontian, and so 

 is the red color produced in the candle, although it is not easy to understand how the 

 muriatic acid should decompose the sulphate of either of these earths, contrary to the 

 order of the affinities, unless indeed it has prevailed by quantity ; or, by mere possi- 

 bility, some carbonate of strontia may have been present. There can be no doubt 

 that mineralogical and physical characters may settle the question, and probably it 

 is settled before this between these gentlemen : if not, chemical trials will undoubt- 

 edly bring it to an issue. — Ed. 



*The stick should be blunt and brushy at the end which is inserted into the pow- 

 der and flame, in order to exhibit this character to the greatest advantage, but it ia 

 not absolutely necessary. 



Vol. XVIIT.— No, 1. 14 



