MINERAL CONCHOLOGY. 419 



ly way in which you have advocated what appears to me to 

 be the true and lasting interest of science, — the encouragement 

 of original publications, in opposition to the specious but 

 fleeting advantages which cheap piracies possess. Such 

 works only tend to convert what would otherwise be a flow- 

 ing stream, into a stagnant lake, by cutting off the springs 

 which had given it life. 



Mons. Agassiz has, however, proposed to revise and cor- 

 rect the work in question ; a proposal which, if earned fully 

 into effect, would certainly be beneficial to the study of Geo- 

 logy : but in many instances it will be found that his transla- 

 tion perpetuates the errors of the original. 



The following short history of the work will explain why 

 revision and correction are necessary, and also account for 

 the inequalities (justly observed by M. Agassiz) which occur 

 in the execution of the different parts of it. This statement 

 is not offered as an excuse for the errors, many of which have 

 been corrected in the later volumes, but to show that such er- 

 rors were mostly unavoidable at the time the work was in pro- 

 gress, and also as being likely to interest all who take a part 

 in the discussion you have excited. 



The first number of the ' Mineral Conchology ' was pub- 

 lished by the late Mr. James Sowerby, in June, 1812, two 

 years before Lamarck's i Systeme' appeared. The author be- 

 ing much more partial to the pictorial department, referred 

 the principal part of the text to his two eldest sons (myself 

 and Mr. G. B. Sowerby), while he executed the plates wholly 

 himself: and he continued his task regularly, even during a 

 long and painful illness, until within three or four days of his 

 death in 1822, when a considerable portion of the fourth vo- 

 lume had been published. For some time previously to this 

 sad event, it had fallen to my lot to describe the whole of the 

 shells, and now I was obliged, in addition, to engrave the 

 plates, a few only having been done in advance by my father. 

 At the conclusion of the sixth volume, circumstances induced 

 me to close the work, with a view to commencing it again in 

 a form more agreeable to the wishes of geologists ; and this 

 intention has not been lost sight of, for a continual expense 

 has been incurred in collecting new materials, and many 

 thanks are due to my friends in responding to my request ; 

 still however the whole of the indexes are not published, and 

 chiefly because I have been induced to give up my time to- 

 wards forwarding the immediate objects of the leading geo- 

 logists of England, by yielding them the best assistance my 

 humble talent would permit. 



The sale of the 'Mineral Conchology' has only been about 



