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146 made a chemical balance. The philosopher speculated loftily about atoms and the nature of things, but he had no practical experience of enamels and pigments and philters and so forth. He was not interested in substances. So Alexandria in its brief day of opportunity produced no microscopes and no chemistry. And though Hero invented a steam engine it was never set either to pump or drive a boat or do any useful thing. There were few practical applications of science except in the realm of medicine, and the progress of science was not stimulated and sustained by the interest and excitement of practical applications. There was nothing to keep the work going therefore when the intellectual curiosity of Ptolemy I and Ptolemy II was withdrawn. The discoveries of the Museum went on record in obscure manuscripts and at the Renascence, never, until the revival of scientific curiosity reached out to the mass of mankind.

Nor did the Library produce any improvements in book making. That ancient world had no paper made in definite sizes from rag pulp. Paper was a Chinese invention and it did not reach the western world until the ninth century a.d. The only book materials were parchment and strips of the Papyrus reed joined edge to edge.