ELECTRIC TELEGRAPHS. 407 



each of which represented either a letter of the alphabet or a numeral^ 

 and by means of this voltaic pile the identical original instrument 

 was able by attaching the ends of two wires to these little brass 

 spots to cause gases to be evolved from these two points hydrogen 

 from one, oxygen from the other, hydrogen being evolved in greater 

 quantity ; hydrogen always indicated the first letter sent. Supposing 

 he wanted to send the word " now :" by putting the hydrogen point to 

 " n" and the oxygen to " o," he made a quantity of gas appear from the 

 " n" point and a smaller quantity from the " o" point. And in order 

 to attract attention he devised the first electric alarum a little bell 

 which you see here, which by the evolution of gas caused a ball to 

 drop and started the mechanism ringing as you see there. Here is 

 also some of the identical wire used on that occasion. This was in 

 the year 1809. Very few years afterwards the attention of the Russian 

 Baron Schilling was attracted to this instrument of Sommering's, and 

 he developed a form of instrument based, not upon the decomposition 

 of water, but upon the deflection of the magnetic needle in face of the 

 current. This is one of the forms of Schilling's telegraph. It was 

 used in the year 1830; and passing from that we come to the year 

 1833, when the two great German philosophers, Gauss and Weber, at 

 Gottingen established between the cabinet of the university and the 

 observatory, about a mile and a quarter distant, a telegraph, a copy of 

 which is to be seen in the room downstairs. It is too bulky to bring 

 up here, but it is well worth a visit as being one of the most valuable 

 historical instruments downstairs. From these two instruments, about 

 the year 1836, Mr. William Fothergill Cooke, who was studying at 

 Heidelberg, heard a lecture delivered on the art of telegraphy. He at 

 once grasped the idea. He came to England and associated himself 

 with Sir Charles Wheatstone, and the two together brought out the 

 first needle instrument used in England. This is the identical instru- 

 ment brought out on that occasion, and here you will see that there 

 are five needles suspended in a line. Each of these needles has two 

 movements the one to the left, the other to the right ; and when two 

 of these are deflected their line of convergence always points to a 

 letter. When, for instance, this last needle is diverging in this direc- 

 tion and this one in the other, they point to the letter " a," when the 

 first and the fourth are deflected they point to the letter " b," the first 



