THE TELEGRAPH. 
INTRODUCTION. 
We need not inform our readers that the purpose of the 
telegraph is the communication of thought at very great dis¬ 
tances. That telegraph is the best which accomplishes the 
operation in the shortest possible space of time. 
In order to convey thought to a distance we must express it 
in signs which shall affect the senses at the distant point. 
In order to convey it rapidly, the sensible signs expressing it 
must be produced as rapidly as thought itself, and they must 
succeed each other without delay. 
The science whose application constitutes the telegraphic art, 
comprises therefore the study of three main problems : — 
1. To discover that physical agent which is most rapidly 
transmitted to the greatest distances, and is there capable of 
impressing our senses by its action. 
2. To contrive a system of signals in which the manifesta¬ 
tions of that agent are rapidly transmitted and are likewise 
varied. 
3. To express thought by means of these signals in the 
quickest, clearest, and most general manner possible. 
These three problems resolve themselves into an infinite 
number of important and difficult questions, worthy of being 
the subjects of many experiments, and of special investigation 
which might occupy a lifetime, and enrich science by new dis¬ 
coveries. But to make these facts practically available in 
telegraphic art, all the above-mentioned problems must be 
studied and solved together ; for if we lose sight of any one of 
them, the results we may obtain will probably be incapable of 
useful applications. 
B 
