On Winter Gardens. 71 



to point out, having perhaps already protracted this paper 

 beyond due bounds. But my wish is, that those whose proper 

 business it is would publish such catalogues in those works 

 which are in every one's hands, and direct the attention of 

 proprietors and gardeners to those plants which, if known, are 

 not pointed out to the ignorant ; urging further the advantages 

 of such an improvement, and adding such details respecting 

 choice, disposition, succession, and so forth, as would here, 

 and in hands like the present, be misplaced. 



I am, &c. 



J. Mac Culloch. 



On the Construction of the Galvanic Battery. 



I beg leave to present to the Editor of the Quarterly Journal 

 an account of a galvanic battery invented by myself some 

 years since, which has been adopted by several of my country- 

 men of the United States of America, and approved by many 

 chemists in Paris, who have seen its operation. 



The general description is this: — The copper plate is formed 

 into a narrow cell in which the zinc is inserted and prevented 

 from contact by bits of - varnished wood. A number of pairs 

 thus arranged are suspended from a common bar of wood by 

 wires, the communication being made as usual between each 

 zinc and the contiguous copper by a metallic slip. It is easy 

 to see that by plunging the cells into a vessel containing the 

 liquid until they are filled, and lifting them out, the instrument 

 will be in action, which may be suspended by emptying them, 

 and again renewed by filling them in the same manner. The 

 facility of operation is greater than that of any other form I 

 have ever seen, and a great power is saved by their complete 

 insulation ; in addition to which, the necessity of separate cells 

 of glass, porcelain, &c. is superseded, which are expensive, 

 troublesome, and fragile. The instrument may be constructed 

 by any tin worker ; and the zinc plates, when worn, can be 

 renewed at a very trifling expense. 



I shall pass on to the minute description, for which purpose 

 I send drawings. 



