262 ANNUAL OP SCIENTIFIC DISCOVERT. 



enormous depositions of silica, ofliine, of peroxide of iron, in the sili- 

 ceous fossil strata, in tripoli, in chalk, and in bog-ores, to the vital pro- 

 cesses of primeval Infusoria ; as if the formation of these enormous 

 geological strata could be effected solely by the vital principle ! But 

 they have altogether overlooked the circumstance, that chalk, silica, 

 and peroxide of iron, must first be present, as the necessary conditions 

 of the life of these creatures before they could be developed ; and that 

 their constituents at the present moment are never absent from the 

 sea, the lakes and the marshes, where the same forms of animalcuke 

 occur in a living state. The water in which these primeval Infusoria 

 lived contained the silica and the chalk in solution, and in a condition 

 perfectly suitable for their deposition, in the form of marble, quartz, 

 and other similar mineral masses ; and this deposition would have 

 taken place inevitably in the ordinary manner, if the water had not 

 contained the putrefying and decaying remains of preceding races of 

 animals, and in them the other conditions of the life of siliceous and 

 calcareous Infusoria. 



Without a combination of these circumstances the presence of 

 these substances constituting the conditions of their existence 

 none of these species of animalculse would have propagated and in- 

 creased to form these enormous masses. These infusorial animalcules 

 can only be considered accidental media of the form which the minute 

 particles of these depositions exhibit ; accidental, inasmuch as, even 

 without these creatures, depositions of the silica, the lime, the perox- 

 ide of iron, would have taken place. Sea-water contains the lime of 

 the coral animals, of the innumerable mollusks existing in this medium, 

 in the same form and condition as it is contained in the lakes and 

 marshes, in which the chalk animalculae develop themselves, or those 

 mollusks the shells of which constitute the Muschelkalk formations. 

 Liebig Letters, 3d edition. 



ON THE LAW OF DEPOSIT OF THE FLOOD TIDE. 



AT the American Association, Cincinnati, a paper was presented by 

 Lieut. C. H. Davis, U. S. N., " On the Law of Deposit of the Flood 

 Tide." This communication was intended to be supplementary to Lieut. 

 Davis' former paper before the Association,* and in some degree ex- 

 planatory. It was as follows : " In my memoir on the geological action 

 of the flood tide," says Lieut. Davis, " I stated that the deposits which 

 are constantly accumulating upon every alluvial coast are increased, or 

 have their growth, in the direction of the flood stream. In proof of this, 

 numerous instances were cited of such growth, or accumulation, on the 

 south coast of the State of Massachusetts ; and this controlling effect of 

 the flood current was further exemplified by the drift of the materials 

 of wrecked vessels, which was found to be always in the same direction, 

 that is, in the direction of the flood current. Since the memoir referred 

 to was written, additional instances have been collected, equally well 

 authenticated and important, and all tending to confirm the conclusion 

 laid down in that paper. In my inquiry into the mechanical action 



* See Annual of Scientific Discovery, 1550, vol. I. 



