STATE OF SCIENCE—COMPTON 399 
Arthur M. Schlesinger in his chapter on midcentury America ? 
gives us the following picture of midcentury economy: 
The amount of capital invested in manufacturing (including fisheries and mines) 
doubled, totaling more than a billion dollars on the eve of the Civil War. First 
in order of importance was the making of flour and meal, then boots and shoes, 
cotton textiles, and lumber products, with clothing, machinery, leather and 
woolen goods forging rapidly to the fore. In 1849, for the first time, the patents 
granted for new inventions passed the thousand mark, to reach nearly six times 
that number in 1860. 
He also points out that ‘of the new mechanisms employed in in- 
dustry the census officials in 1860 characterized the sewing machine 
as an altogether ‘revolutionary instrument.’ ”’ From where we stand 
today, it is difficult to realize that a century ago perhaps the most 
significant tool in American industry was the sewing machine. 
With respect to science and invention, the world at the last mid- 
century stood at the threshold of far-reaching and significant dis- 
coveries which were to render the ensuing century unparalleled in 
human progress. 
Whitehead has observed that the greatest invention of the nine- 
teenth century was the invention of the method of invention. He 
goes on to say, “in order to understand our epoch, we can neglect all 
the details of change, such as railways, telegraphs, radios, spinning 
machines, and synthetic dyes. We must concentrate on the method 
itself, that is the real novelty which has broken up the foundations 
of the old civilization. The prophecy of Francis Bacon has now 
been fulfilled; and man, who at times dreamt of himself as a little 
lower than the angels, has submitted to become the servant and 
minister of nature.” 
In physics, at the last midcentury, the scientific world stood firmly 
on the solid foundation of Newtonian mechanics, unaware that just 
ahead a series of events was taking shape which would effect a revolu- 
tion in traditional thinking. In electricity, the basis had been laid 
by Franklin and Volta, while Oersted, Faraday, and Henry had 
shown the relation between electricity and magnetism. Fresnel had 
established the wave theory of light, and Joule had just proven the 
equivalence of heat and work. 
But in 1850 the great evolution of the science of physics was about 
to begin. Robert A. Millikan summarized these events last year on 
the occasion of the centennial of the American Association for the 
Advancement of Science by mentioning three great advances: (1) 
the establishment by Joule, Kelvin, Mayer, and Helmholtz of the 
first and second laws of thermodynamics; (2) the quantitative proof 
of the kinetic theory of gases by Clausius, Boltzmann, and Maxwell; 
and (3) the publication by Maxwell in 1867 of his classic paper on 
2 Political and Social History of the United States. Macmillan Company. New York, 1933. 
