858 NOTES ON THE GEOLOGY 



specific identity with the forms shown in figs. 1, 3, 4, 5, 6, and 7, 

 from Damascus and the Mount of Ohves, Beyroot, and a missionary 

 station on the Upper Mississippi. You will observe in the figures 

 small spots, marked a, a. These were red spots found in the cells ; 

 possibly eggs. They are present both in the Asiatic and American 

 specimens. The other dark spots, b, b, are air bubbles, left in the 

 cells after spreading the specimens in Canada balsam. 



" The scale of the drawings is the same for all. Fig. 6 shows yVti 

 of a millimetre, magnified equally with the sketches. No siliceous 

 infusoria were found in any of the specimens." 



These details seem to me to furnish a most interesting exam- 

 ple of the triumph of science over difficulties, and to hold out 

 great promise to geology from the microscope. The missionary, 

 as he hurries over unexplored regions on his horse, or on his 

 camel, breaks off a few specimens of the rocks he meets, giving 

 them a place, perhaps, in his wardrobe ; * and at length sends 

 them to me, five thousand miles distant, with a label, merely indi- 

 cating the locality. I inclose eight or ten specimens in a letter to 

 Prof. Bailey, through the mail, so minute, that the most sagacious 

 postmaster would not suspect their presence, and would not think 

 them a breach of the la\v did he notice them. In a short time 

 the microscope is made to reveal infinitessimal forms in these 

 specimens, which fix their position in the geological scale of rocks, 

 as satisfactorily as if they contained megatheroids or mastodons. 

 In other words, the most difficult problem in geology, the identi- 

 fication of rocks in widely separated regions, is solved at a glance, 

 and at the distance of five thousand miles from the only place 

 where we should suppose it possible to solve it. If this is not a 

 beautiful example of the magic power which science sometimes 

 bestows upon its votaries, I know not where one may be found. 

 In these remarks, I shall of course be understood to refer to the 

 gentleman who has brought out these results ; and not to myself, 



* I have reason to know, that not a few of the specimens in my collection were con- 

 veyed in this manner hundreds of miles, over some of the roug-hest regions of Asia. In- 

 deed, half a suit of clothes, thus freighted, in one instance came into my possession ; and if 

 they had been hung up, with their contents, in my cabinet, they would have furnished an 

 interesting memento of zeal in the cause of science. 



