The Evolution of Tools and Implements. 
WILLIAM D. JOHNSTON. 
Man’s happiness today is dependent upon the comforts with 
which he is surrounded. His home, his clothes, his city, and 
the great complexity of present day society are the things 
that make life desirable. The society of which he is a part is 
dependent for its existence upon a great multiplicity of me- 
chanical devices. Thousands of men go to the steel mills each 
morning to care for the great furnaces where millions of tons 
of ore are converted into iron. Thousands of men go to the 
factories to make machinery and tools from the iron. Again, 
men use the tools to make machines—great mechanical 
devices—huge lathes capable of turning an engine wheel; dry 
docks to float the longest ship; valves through which an auto- 
mobile can pass—it is upon these things we depend today. 
They did not come suddenly, but through long, continual in- 
ventive effort to use the materials at hand to the greatest 
advantage. 
Before the invention of metals, man’s supply of materials 
with which to work was the flint quarry, the gravel bank, 
and the chert ledge. His weapons and tools were made of 
stone; at first in the pieces just as they were picked up; later 
‘they were roughly chipped, and in the time just preceding the 
invention of bronze they were elaborately chipped, polished 
and often carved. 
When man discovered that copper and copper and tin alloys 
would lend themselves to shaping quickly by pounding, and 
that the weapons so made could be ground to an edge much 
sharper than that obtainable in stone, he did not hesitate to 
discard the quarry for the mine. His stone implements were 
reproduced in bronze and improved as _ the _ tough- 
ness and malleability of the metal suggested. His daggers 
were longer, his axe shorter and less unwieldly, and his arrows 
had sharper points. 
The supplies of bronze were limited, and hence its use was 
not greatly extended. It was only with the invention of iron 
smelting processes that man entered into the era of invention 
and manufacture whose comforts today we enjoy. With such 
supplies of metal at hand there was no limit to the advance- 
ment of mechanical invention. Steel followed as a logical re- 
