86 ANNUAL OF SCIENTIFIC DISCOVERY. 



that it was the only gold medal which the Institute had ever 

 awarded. The following experiments were made on Monday, 

 llth July, 1870 : 



1. Transmission by atmospheric compression by means of the 

 large machine, obtaining answers by impulsion and repulsion, 

 Signer Guattari having at present but one machine. 



2. System of impulsion and repulsion by a naval apparatus, 

 which may be used with 5 different derivations or branches. 



3. Universal telegraphy, namely, dispatch telegrams to one or 

 more stations at the same time without the aid of the transmitting- 

 machine, or the necessity of the sender remaining fixed to any 

 one point. Nature. 



THE NEW CABLE BETWEEN ENGLAND AND FRANCE. 



The new cable for the Submarine Telegraph Company, to be 

 laid from Beechy Head to Cape Antifer, near Havre, a distance 

 of about 70 miles, has been commenced at Mr. Henley's works, 

 at North Woolwich, and will soon be completed. It forms a 

 large, massive cable, and will be one of the largest yet manufac- 

 tured. The core consists of 6 insulated conductors, wound and 

 served in the ordinary manner; each conductor is a strand of 7 

 wires, weighing 107 pounds per nautical mile, and insulated with 

 3 coatings of Chatterton's compound, and 3 of gutta-percha to 

 the weight of about 150 pounds per mile. The severed core is 

 sheathed externally with 12 No. O.B.B. galvanized iron wires, 

 protected with 2 servings of tarred hemp and bituminous com- 

 pound. The shore ends have a similar core, but are sheathed 

 with 12 No. 0000 B.B. galvanized iron wires, protected with 2 

 servings of hemp and compound. This is the first time wire of 

 such enormous diameter has been used for submarine cables. 

 Land lines for this cable are being erected between London and 

 Beechy Head, and Havre and Paris, so that the new line will be 

 an independent one, and will tend to obviate, if not prevent, the 

 delays which have frequently occurred in the transmission of mes- 

 sages between London and Paris, arising chiefly from a pressure 

 of business. In future any breakage which may take place in 

 the old and new lines will be quickly repaired, because, under the 

 authority given lately, the company will conduct repairs with 

 their own repairing ship, instead of employing a tug as hitherto. 

 Van Nostrancfs Eng. Mag. 



PROFESSOR HENRY OF THE SMITHSONIAN INSTITUTE ON LIGHT- 

 NING RODS. 



In answer to a letter of inquiry as to the best method of erect- 

 ing and constructing lightning rods, Professor Henry gives the 

 following instructions : 



1. The rod should consist of round iron of about one inch in 

 diameter ; its parts, throughout the whole length, should be in 



