26 INTRODUCTION. 



Of the books in our own language, after deducting those which are 

 obsolete, or worthless, there still remain probably 50,000 volumes, 

 which would repay a perusal. Supposing then a person to read 

 100 pages a day, or 100 volumes a year, which is more than could 

 well be retained and digested, it would require 500 years to read all 

 the books worth reading, in the English language alone ! This result 

 shows the importance of selection in our reading; or we may misdi- 

 rect our powers, and misemploy our time, by dwelling on inferior 

 works, and neglecting the nobler and more useful. 



Encyclopaedias. 



From the great multiplicity of books on all subjects of knowledge, 

 arises the utility of Encyclopedias ; which, as sources of general 

 information, deserve here a distinct notice. Their name is derived 

 from the Greek wideta, learning, from van, a youth ; and iyKVK\tos, cir- 

 cular, from KVK*OS, a circle ; hence it may be defined, the circle of 

 learning Their object is to give a summary of human knowledge ; 

 extracted and digested, for the most part, from various works ; and 

 accompanied by references to the best authors, on every subject. 

 They are valuable works for occasional use ; but most of them are 

 too imperfect to be relied upon ; either as giving all the information 

 sought; or the latest information, on subjects which are liable to 

 change or susceptible of improvement. 



The earliest summary of human knowledge, appears to have been 

 the books of Hermes, preserved with great care by the Egyptians, 

 and which may be called the Hermiana. Hermes or Mercurius 

 Trismegistus, is the classic name of the Egyptian Thaut, (Thot, 

 Thoth, Thoyt, Theut, or Taaut,) supposed to have been the son of 

 Misraim, and grandson of Ham. He is said to have invented gram- 

 mar, arithmetic, geometry, astronomy, medicine, and music ; and to 

 have engraved his knowledge on pillars of stone. But as the same 

 Egyptian word signifies also a pillar or monument, as well as its 

 guardian deity, the name has doubtless been applied generally to the 

 learning of the Egyptian priests, preserved in monumental inscrip- 

 tions. Of the forty-two books ascribed to Hermes, some are 

 preserved, including some which are spurious : while others are 

 lost. They treat of the studies above mentioned, together with 

 religion, government, and natural history, as then known. 



Similar to these are the twenty-one books of the Persian Zenda- 

 vesta, or living word, written by Zoroaster, otherwise called Zer- 

 dusht. The Persians comprehended all knowledge under the term 

 Magia; and the term magus was synonymous with philosopher or 

 wise man. The Chinese also are said to have an ancient work 

 called Tay Tsing, or San-tsae-too-koey, which treats very fully and 

 systematically of all subjects with which they were acquainted. The 

 only general works left us by the Greeks and Romans, worthy of 

 mention here, are those of Aristotle and Pliny. Aristotle wrote on 

 almost all subjects known to the Greeks, but in various detached 

 treatises : while the Natural History of Pliny, though not an exact 

 work of science, : .s a valuable compendium of ancient learning. 



Some works of a general nature were published in the middle 



