PREFACE 



No apology ought to be required for the appearance of a work like 

 this : the importance of the subjects discussed should secure at least an 

 impartial examination. 



But from the humiliating consciousness which the author feels of his 

 own inability to do justice to so difficult a task, he is induced to say 

 something by way of explanation, in order if possible, to put himself 

 upon friendly terms with his readers. The importance of an enter- 

 prise, however, furnishes no reason to an incompetent person for at- 

 tempting its prosecution. 



If, after the book has passed the trial of the public prosecutors in be- 

 half of science, the critics, they shall decide against it, the author has 

 no alternative, but must plead guilty: neither will he claim indulgence 

 on the ground of its being the first offence, or plead, in extenuation of 

 his fault, his ignorance of the law in relation to the case. 



But a sincere desire, (augmented by personal considerations,) to aid in 

 the diffusion and cultivation of science, has induced him to make au 

 effort, which may not be regarded by liberal minds as altogether in- 

 excusable. 



The practice of issuing crude and imperfect books, is a fault quite 

 too prevalent at the present day : there are already too many mere 

 alphabets of science, abridgements, and books of learning made easy ; 

 their tendency is to make conceited and superficial scholars, without 

 the labor of personal observation and patient study. 



But the elements of any science may be so explained and arranged, 

 as to give a synopsis which may be of much service to the student ; 

 and when these elements are learned, he has laid the foundation for 

 future advancement by his own observation. Plainness and brevity have 

 been studied, and technical language avoided as much as possible ; a 

 glossary has been appended which explains such technical terms as 



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