Lenglet du Fresnoy, one of the greatest readers, calculated that he could not read, with satisfaction, more than ten hours a day, and ten pages in folio an hour; which makes one hundred pages every day.  Supposing each volume to contain one thousand pages, every month would amount to three volumes, which make thirty-six volumes in folio in the year.  In fifty years a student could only read eighteen hundred volumes in folio.  All this, too, supposing uninterrupted health, and an intelligence as rapid as the eyes of the laborious researcher.  A man can hardly study to advantage till past twenty, and at fifty his eyes will be dimmed, and his head stuffed with much reading that should never be read.  His fifty years for eighteen hundred volumes are reduced to thirty years, and one thousand volumes!  And, after all, the universal historian must resolutely face thirty thousand volumes!

But to cheer the historiographer, he shows, that a public library is only necessary to be consulted; it is in our private closet where should be found those few writers who direct us to their rivals, without jealousy, and mark, in the vast career of time, those who are worthy to instruct posterity.  His calculation proceeds on this plan, that six hours a day, and the term of ten years, are sufficient to pass over, with utility, the immense field of history.

He calculates an alarming extent of historical ground.

For a knowledge of Sacred History he gives 3 months. 
Ancient Egypt, Babylon, and Assyria, modern Assyria}
or Persia } 1 do. 
Greek History 6 do. 
Roman History by the moderns 7 do. 
Roman History by the original writers 6 do. 
Ecclesiastical History, general and particular 30 do. 
Modern History 24 do. 
To this may be added for recurrences and re-perusals 48 do.
____
The total will amount to 101/2 years.

Thus, in ten years and a half, a student in history has obtained an universal knowledge, and this on a plan which permits as much leisure as every student would choose to indulge.

As a specimen of Du Fresnoy’s calculations, take that of Sacred History.

For reading Pere Calmet’s learned dissertations in the}
order he points out } 12 days
For Pere Calmet’s History, in 2 vols. 4to (now in 4) 12
For Prideaux’s History 10
For Josephus 12
For Basnage’s History of the Jews 20
——­
In all 66 days.

He allows, however, ninety days for obtaining a sufficient knowledge of
Sacred History.

In reading this sketch, we are scarcely surprised at the erudition of a Gibbon; but having admired that erudition, we perceive the necessity of such a plan, if we would not learn what we have afterwards to unlearn.