370 Bihliogra'phy. 



2. Address delivered at the annual meeting of the Boston Natural 

 History Society, May 5th, 1841 ; by J. E. Teschemacher. Boston, 

 pp. 46, 8vo. — This well-written discourse is chiefly occupied with a 

 sketch of the recent progress of the different branches of natural history, 

 beginning with zoology, and ending with mineralogy and geology. In 

 such a wide range, it is obviously impossible, within the limits of an 

 ordinary address, to give more than a glance at some of the promment 

 discoveries and most interesting facts in each department; indeed, 

 nothing beyond a mere outline could be expected from a single person, 

 without great expense of time and labor. The author offers the fol- 

 lowing pertinent remarks upon the prevalent idea ; that these sciences 

 become essentially more difficult as they attain a higher degree of per- 

 fection, so that it is almost hopeless for a man of common leisure and 

 intellect successfully to prosecute their study, or even to keep pace 

 with the march of discovery. 



" That the accumulation of facts and objects of interest in every science is great, 

 cannot be denied ; but it is also certain that every discovery, every approach to 

 truth, dissolves the clouds of error in which a science may be enveloped, and 

 instead of making it more intricate, simplifies and renders it more amenable to the 

 commonest understanding. The process is clearly this ; the great accumulation of 

 facts in any science, causes an absolute necessity for arrangement into divisions and 

 subdivisions; the more extensive the knowledge and the number of the facts, the 

 move natural, the more clearly defined and simple are these divisions, and each 

 becomes the object of a separate study ; hence, the subject is more easily mas- 

 tered, more easily grasped by the mind, while the man of comparatively little 

 leisure can undertake a single division and not only keep pace with discovery, but 

 even add something to what is already known. 



" In botany, for instance, how few students are acquainted with the cryptoga- 

 mous plants, and of those who are, how few know much of the ^Igcc or sea-weeds. 

 In each of these divisions of the vegetable kingdom, the facts have accumulated so 

 much as render it sufficient for a separate study. So in chemistry, how little was 

 formerly known of the chemistry of organic bodies : there is now sufficient to make 

 it a division of great importance and separate study. And in geology, how few 

 geologists are well versed in that most interesting portion, fossil vegetation. The 

 person who would attempt to embrace at once any extensive branch of natural 

 history as a whole, might just as well endeavor to learn the dictionary of a lan- 

 guage by heart; but taken in detail, division by division, there is much less diffi- 

 culty in obtaining insight into science than formerly, while separate fields are 

 thereby offered to the increased number of laborers, where each may expect to reap 

 a reward. Indeed, the concentration of the whole attention on one division has 

 been the evident cause of many brilliant discoveries. Let no one, therefore, be 

 discouraged by the idea that science is more difficult of attainment now than for- 

 merly ; it is in fact less so, as can be readily testified by those who have had to 

 unlearn the eirors they had previously counted on as truths, and noticed the sim- 

 plicity which the removal of these always introduces." 



We would observe, if we may hazard a passing observation upon 

 the question, that these sciences, like most other branches of knowledge. 



