Naturally the enormous expense stood in the way of any extended development.

The same thickness also interfered with cable extension.

Only about a hundred wires could be squeezed into one cable, against the eighteen hundred now compressed in the same area.

Because of these shortcomings, telephone progress, about 1900, was marking time, awaiting the arrival of a thin wire that would do the work of a thick one.

The importance of the problem is shown by the fact that one-fourth of all the capital invested in the telephone has been spent in copper.