226 Letters of Mr. Brongniart, with remarks. 



Ducald. I have discovered characters sufficiently distinct 

 to establish a particular species, remarkable for the large- 

 ness of the eyes, and which I denominate Calymene macrohp- 

 talme. I learn from these specimens, and from some 

 others which I have received, in different ways — that trilo- 

 bites exist in America, as well as in Europe, that the ani- 

 mals differ very little (if indeed they constantly differ at all) 

 from those of Europe, and that they are, in both cases, found 

 in the schists phyllades, or in the transition limestones, or 

 at least, in those which are very ancient. 



"But sir, these are only first impressions; I address 

 them to you, and to all the American geologists, that you 

 and they may enable us either to reduce them to certainty 

 or to abandon them. 



" My son who accompanied me into Italy, and who (as' 

 observed in a former letter) is more particularly devoted to 

 Botany, continues his researchupon the determination of fos- 

 sil plants. You were so good as to send me pieces, which in 

 relation to this subject were very curious, but, unfortunately 

 the impressions were not sufficiently diversified or exact, to 

 determine the differences and resemblances of the plants, 

 belonging to the coal formations of Europe and America. 



" I must then again commend myself to your zeal for the 

 advancement of the sciences, and to your kindness towards 

 myself. I shall here terminate this letter, which, already 

 too long, would be much more extended still, if I were only 

 to glance at the various subjects for reflection which my late 

 travels have presented." 



Thus we have taken, we trust, not an improper liberty 

 with the letters of Mr. Brongniart. We have made the 

 most important parts of them public, because we believed 

 we could in no way so effectually promote his liberal and 

 laudable views, as by exhibiting them in his own language. 

 In addition to the observations upon this subject on page 7 

 of this volume, we would say, that geological deductions 

 drawn from the comparison of a great number of particu- 

 lars, collected from many different countries, exhibit a good 

 example of the Baconian or inductive course of reasoning, 

 and afford us the fairest prospect of arriving at truth. Such 

 a research is as different from the visionary hypotheses with 

 which geology formerly abounded, as the analytical course 

 of modern chemistry, is from the ancient assumption of the 

 four elements. 



