This was at a time, not very long ago, when it was hardly respectable to be an inventor; when, even though men admitted that some inventors had done valuable work, the work was supposed to be largely a chance shot of a more or less crazy man.

Yet Ericsson was an inventor--though he was an engineer.
So were Sir William Thompson (afterward Lord Kelvin), Helmholtz, Westinghouse, and a very few others; so are Edison and Sperry.
Many inventors, however, live in their imaginations mainly--some almost wholly.

Like Pegasus, they do not like to be fastened to a plough or anything else material.

Facts, figures, and blue-prints fill their souls with loathing, and bright generalities delight them.
The engineer, on the other hand, is a man of brass and iron and logarithms; in imagination he is blind, in flexibility he resembles reinforced concrete.

He is the antipodes of the inventor; he despises the inventor, and the inventor hates him.