RECENT PROGRESS IN PHYSICS. 



371 



Fig. 9 represents the rubber as seen from the 

 amalgamated side «'f the leather, with its two 

 flaps "of oiled silk, t being single and u double. 



With remarkable power. Winter's machines 

 combine, as we have just seen, great simplicity 

 of construction. 



The following are the prices of Winter's machines, with the dis- 

 charger : 



Machines of similar construction and equal power, but less elegantly- 

 finished : 



Size of plate. 



Price. 



Florins con. 



U.S. 



18 inches. 

 15 inches. 

 12 inches. 

 10 inches. 



8 inches. 



6 inches. 



50 

 40 

 30 

 20 

 16 

 10 



$25 



20 



15 



10 



8 



5 



Winter has really displayed great taste in the arrangement of elec- 

 trical apparatus, and has given a new and better form to many elec- 

 trical experiments and toys. 



He has constructed Lcyden jars of extraordinary striking distance, 

 of which more will be said in another place. 



That he has succeeded in telegraphing and in kindling powder at 

 a distance of 15,600 feet with frictional electricity, shows with how 

 much certainty he can experiment with his apparatus. 



I have satisfied myself in Vienna as to the power of the machines 

 made by Winter. With the greatest readiness he has, at my request, 

 furnished me the opportunity of giving the above description of his 

 machines. 



Gruel, of Berlin, makes cylinder machines of a peculiar construc- 

 tion, which are said to be of great power ; but of this I know nothing 



