* PREFACE. 



fluence of new systems, and modes of thinking, 

 might be exhibited with greater advantage, and 

 perused with more satisfaction. 



As the author aimed at nothing more than a 

 brief retrospect of the period to which this work 

 is devoted, it was impossible for him to do more, 

 consistently with his plan, than to mention the 

 principal discoveries, inventions, improvements 

 and writers, under each head; and even these 

 could only be noticed with great brevity, and in 

 very general terms. To have attempted minute 

 details, and particular explanations, would have 

 extended the work to many volumes. With respect 

 to the choice which has been made of facts and 

 names, the degree of importance ascribed to them, 

 and the proportion of room and attention allotted 

 to each^ different readers will, no doubt, entertain 

 different opinions. Everyone will be apt to suppose 

 that the particular names and studies to which he is 

 most attached, are not noticed with sufficient re- 

 spect, or dwelt upon at sufficient length. The au- 

 thor can only say, that, in general, he indulged 

 in more or less prolixity, according to his ideas 

 of the importance of the several subjects, the ex- 

 tent of his acquaintance with them, or the degree 

 in which they interested his own mind. That from 

 such a multiplicity of objects, he often selected 

 injudiciously, and made an erroneous estimate of 

 their comparative value, is altogether probable. 



Althouj^h the very nature of the work required 

 that all the subjects brought into view should be 

 treated superficially, and that nothing more than 

 rapid outlines should be attempted; yet the intel- 

 ligent reader will, doubtless, discern, that the mode 

 of treating some of the subjects manifests a very 

 small and paitial acquaintance with them. For the 



