.206 Telephone Systems of the Continent of Europe 



under a distinct obligation to concede a ' record ' to our Berlin 

 friends. As the difficulty is not one that causes trouble elsewhere, 

 it is presumably due to faulty arrangement of parts in the German 

 instruments. When ringing batteries are used, the cells, eight to 

 twelve in number, are contained in a small cupboard placed on the 

 floor immediately below the instrument. The cupboard is about 

 two feet high, and has a veneered front of decorative wood, with 

 ornamental mouldings, so as to look somewhat like a piece of 

 ordinary furniture. The automatic switch is of Morse-key 

 pattern, with top and bottom anvil contacts, a form which, it 

 will be remembered, was adopted in the American instruments of 

 1879 and 1880, and which was speedily abandoned in favour of 

 rubbing surfaces owing to the facility with which the original 

 ones choked with dust. The transmitters are most often of the 

 familiar Mix & Genest type, two carbon blocks, mounted on a 

 vertical wooden diaphragm, carrying three horizontal pencils 

 backed by silk or felt packing and an adjustable spring ; but 

 there is also a transmitter by Siemens & Halske, which consists 

 of a flat disc of carbon, about one and a half inches in diameter, 

 attached to a vertical diaphragm and touching a similar disc 

 placed behind it, but with its face cut into lozenge pattern so as 

 to offer thirty-four flattened points to the pressure of the front disc. 

 The intimacy of contact between the two plates is adjustable by a 

 screw behind the back disc. This transmitter speaks loudly, but 

 the tone is inclined to be harsh. The receivers are universally of 

 Siemens & Halske's admirable double-pole type (but supplied 

 by all the firms), which has been often described, and which for 

 many years served the German Post Office as transmitters also. 

 It was this instrument which enabled the Mutual Telephone Com- 

 pany, Limited, to open its Manchester exchange in 1891, before 

 the expiry of the transmitter patents, and to obtain better speak- 

 ing on its metallic circuits than the National Telephone Com- 

 pany could manage with Blake microphones and single wires. 

 But when used as a receiver its weight (23 ozs.) and shape do not 

 commend it to those who have been accustomed to light receivers 

 of more elegant form. It will be noticed that no desk on which 

 a writing pad can be placed is provided, so that notes of a con- 

 versation cannot be taken, and the use of reference books or papers 



