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A week later the same telephones were used in tests between Sydney and Maitland.THE FIRST TELEPHONE EXPERIMENTS IN SYDNEY, AUSTRALIA JANUARY 1878 CONTINUED Page 2Mr. E. C. Cracknell , Superintendent of Telegraphs,assisted by Mr. G. Kopsch of that Department, has constructed an instrument with which experiments were made on Saturday between
La Perouse (near the North Head, Botany Bay) and Sydney, attended with very great success. the instrument has been manufactured upon a principle somewhat similar to that of Professor Bell's of America, and consists of a permanent bar magnet at the end of which is a coil of very fine silk-covered copper wire, having an electrical resistance of about 70 ohms surrounding a core of soft iron, which is screwed on to the magnet; at a short distance from the free end of the soft iron core a metal disc is placed with a screw adjustment for regulating the waves of current which are produced, the disc is enclosed in a sounding box through an aperture in which the sounds are passed.
The experiments on Saturday were made over a circuit of ten miles. Mr. Cracknell and Mr. Taylor, Superintendent of the New Zealand cable, were at La Perouse, whilst Mr. Kopsch and Mr. Wilson officiated at the Sydney end. Conversation was carried on uninterruptedly for a considerable time, when one of the gentlemen in Sydney played a tune upon a mouth harmonica, which was distinctly heard at La Perouse. In response Mr. Taylor sang 'We sat by the River, you and I', followed by 'Little Footsteps', the words of which were distinctly
audible. A bugle was played with equally good results, and other sounds were transmitted without difficulty.
In the present state of our knowledge of this feature in telegraphy we have not yet succeeded in bringing the telephone to the state of perfection necessary for its practical application, but it is believed that the principle which has just dawned upon us will be so worked out by our scientific men as to bring it to bear upon our every day system of telegraphic communication.
We congratulate both Mr. Cracknell and Mr. Kopsch upon the success which so far attended their efforts in this direction, and we may take credit to ourselves in that we are not behind other places in the progressive march of science."
These experiments were officially sponsored, not only out of scientific curiosity but also to see what effect the telephone might have on the business of the Electric Telegraph Departments. The general conclusion was that the departments could not make any use of them at their present state of development, nor were they likely to be a serious competitor until greatly improved.
This
was hardly surprising since the performance was comparable to a conversation
between two people at a distance of between 100 & 500 metres. Speech
was difficult, loud singing was more easily recognised, and only the sounds
of loud musical instruments were effectively transmitted, Even so, the
use of a bugle seems like overkill.
The instruments used in the experiments in 1878 were not complete telephones. A single device was used at each end of the line capable of acting either as a transmitter or a receiver so while a man at one end held the device to his ear, the man at the other shouted, screamed or sang at his. The experiments were controlled by morse code signals which used a separate e line if possible, or else the one line was switched alternatively between the telephones and telegraph instruments.
These instruments were copied from descriptions in the technical press, similar to the one quoted earlier, they were the prototype of the magnetic receiver used universally in telephones for the next seventy years. However, as a transmitter it left much to be desired and was soon superceded by various types of carbon microphone.
