'Mr. Seybert''s Analysis of Glassy Actynolite, 331 



attract fine iron filings, so long as the apparatus remains in 

 the dilute acid, but instantly loses that power when with- 

 drawn from the liquid. One curious result is presented by 

 this apparatus, which we should not have anticipated from 

 experiments made by myself with common electricity, and 

 which I sent to you when I last wrote, nor from the experi- 

 ments of Mr. BowEN, with Hare's calorimotor; it is this : 

 when the spiral brass wire passes from right to left, the 

 north pole is found on the negative or copper end; if from 

 left to right, that pole is found on the positive or zinc end; 

 this effect is like that noticed by Va7i Beck. It certainly in- 

 dicates another point of difference, which Dr. Hare justly 

 asserts to exist between common galvanic instruments and 

 his calorimotor; and the result of Mr. Bowen's experiments, 

 and my own with common electricity, points out an analogy 

 between the effects of the common electrical machine and 

 of the calorimotor. I have tried in vain to communicate such 

 a degree of magnetism to silver and platina wires by this 

 little apparatus as to induce them to assume a north and 

 south direction,- and I have in vain attempted to influence 

 delicately suspended galvanic apparatus by the rays of 

 light separated by a prism ; but I doubt not tiiat some for- 

 tunate philosopher, in possession of a heliostadt, will be able 

 to produce some eff*ect in this way. 



Dartmouth College, Hanover, Jf. H. 



Art. XVI. — Analysis of the Glassy Actynolite from Concord 

 Township, Delaware Co. Penn. By. H. Seybert. 



Color in the mass, emerald green ; powder greenish white. 

 Lustre vitreous. Translucent. Fracture in one direction 

 fibrous, in the opposite irregular. Very frangible. Scratch- 

 es glass. Structure fibrous and fasciculated. Specific gravi- 

 ty 2.987. Fusible, before the blowpipe, into an opake 

 greenish enamel. 



Analysis. 



A. 3 grammes of the mineral, in the state of an impal- 

 pable powder, after exposure to a red heat, with the contact 

 of air, had assumed a reddish tinge, and weighed 2.98 



