J\'otice$ of Vegetable Remains in Coal Strata. 389 



In the above figure, such a current is represented in two 

 sections at right angles to the axis of the wires, when simi- 

 larly electrified, from which it will be apparent that the 

 north and south powers meeting, will attract each other. 



In the following figure, the sections of the wire are shown 



dissimilarly electrified, by which similar magnetic power^ 

 meet, and consequently occasion a repulsion. 



53. JVotices of Vegetable Remains in Coal Strata. 



TO THE EDITOR. 



SIR — The very close resemblance the figures in your 

 last Journal marked C 3 — C 4 — , bear to a remarkable 

 sandstone which occurs abundantly in the coal fields of 

 Scotland, must strike every one acquainted with the latter. 



On the shores of the Frith of Forth are vast quantities 

 of this sandstone in various imitative forms, more com- 

 monly resembling branches of trees. These are seldom 

 less than an inch in diameter, and often exceed four inches. 

 Branches of smaller size are sent off from the larger, and 

 the exterior of all is covered with the impressions so well 

 delineated in Mr. Granger's paper. Although they have 

 been examined by many distinguished naturalists in Great 

 Britain, no satisfactory explanation of them has been pub- 

 lished. The following notice of similar appearances is from 

 Tilloch's Magazine for December, 1820. 



Tour's, &c. 



J. W. WEBSTER. 



" Large Organic Remains. 



" In some of the sandstone rocks which alternate with 

 the seams of coal, in a great many if not in all the coal- 

 fields of England, the remains of very large, thin, hollow or 



