line was drawn.  The want of correct means of measuring time and temperature was severely felt; the clepsydra of Ctesibius answered very imperfectly for the former, the hydrometer floating in a cup of water for the latter; it measured variations of temperature by variations of density.  Philadelphus, who toward the close of his life was haunted with an intolerable dread of death, devoted much of his time to the discovery of an elixir.  For such pursuits the Museum was provided with a chemical laboratory.  In spite of the prejudices of the age, and especially in spite of Egyptian prejudices, there was in connection with the medical department an anatomical room for the dissection, not only of the dead, but actually of the living, who for crimes had been condemned.

3.  For the diffusion of knowledge.  In the Museum was given, by lectures, conversation, or other appropriate methods instruction in all the various departments of human knowledge.  There flocked to this great intellectual centre, students from all countries.  It is said that at one time not fewer than fourteen thousand were in attendance.  Subsequently even the Christian church received from it some of the most eminent of its Fathers, as Clemens Alexandrinus, Origen, Athanasius.

The library in the Museum was burnt during the siege of Alexandria by Julius Caesar.  To make amends for this great loss, that collected by Eumenes, King of Pergamus, was presented by Mark Antony to Queen Cleopatra.  Originally it was founded as a rival to that of the Ptolemies.  It was added to the collection in the Serapion.

Scientific school of the museum.  It remains now to describe briefly the philosophical basis of the Museum, and some of its contributions to the stock of human knowledge.

In memory of the illustrious founder of this most noble institution—­an institution which antiquity delighted to call “The divine school of Alexandria”—­we must mention in the first rank his “History of the Campaigns of Alexander.”  Great as a soldier and as a sovereign, Ptolemy Soter added to his glory by being an author.  Time, which has not been able to destroy the memory of our obligations to him, has dealt unjustly by his work.  It is not now extant.

As might be expected from the friendship that existed between Alexander, Ptolemy, and Aristotle, the Aristotelian philosophy was the intellectual corner-stone on which the Museum rested.  King Philip had committed the education of Alexander to Aristotle, and during the Persian campaigns the conqueror contributed materially, not only in money, but otherwise, toward the “Natural History” then in preparation.