ed boldly
at the start that he would devise a battery without lead, and one in
which an alkaline solution could be used--a form which would, he firmly
believed, be inherently less subject to decay and dissolution than the
standard type, which after many setbacks had finally won its way to an
annual production of many thousands of cells, worth millions of dollars.

Two or three thousand of the first experiments followed the line of his
well-known primary battery in the attempted employment of copper oxide
as an element in a new type of storage cell; but its use offered no
advantages, and the hunt was continued in other directions and pursued
until Edison satisfied himself by a vast number of experiments that
nickel and iron possessed the desirable qualifications he was in search
of.

This immense amount of investigation which had consumed so many months
of time, and which had culminated in the discovery of a series of
reactions between nickel and iron that bore great promise, brought
Edison merely within sight of a strange and hitherto unexplored
country. Slowly but surely the results of the last few thousands of his
preliminary experiments had pointed inevitably to a new and fruitful
region ahead. He had discovered the hidden passage and held the clew
which he had so industriously sought. And now, having outlined a
definite path, Edison was all afire to push ahead vigorously in order
that he might enter in and possess the land.

It is a trite saying that "history repeats itself," and certainly no
axiom carries more truth than this when applied to the history of each
of Edison's important inventions. The development of the storage battery
has been no exception; indeed, far from otherwise, for in the ten years
that have elapsed since the time he set himself and his mechanics,
chemists, machinists, and experimenters at work to develop a practical
commercial cell, the old story of incessant and persistent efforts so
manifest in the working out of other inventions was fully repeated.

Very soon after he had decided upon the use of nickel and iron as the
elemental metals for his storage battery, Edison established a
chemical plant at Silver Lake, New Jersey, a few miles from the Orange
laboratory, on land purchased some time previously. This place was the
scene of the further experiments to develop the various chemical forms
of nickel and iron, and to determine by tests what would be best adapted
for use in cells manufact