•• ' -. * ■;. 



F - 



* 



150 Bibliography. 



last subject, Lieut. Maury has brought forward much thg^as not hith- 

 erto been published, and views of interest to meleorojogical science 

 and navigation, whether they are all sustained or not by^ furiher 

 study. Sonne of the views on the Gulf Stream and the northern cur- 

 rent we find stated as early as the year 1837 in an article in this 

 Journal by Mr. VV. C. Redfield, and in part alluded to in 1835, vol. xxv, 

 p. 13L But great additions have been made to our actual knowledge 

 of oceanic currents and the courses of winds, and greater results 

 promise to reward the skill and energy with which the researches are 

 now prosecuted. We trust that Lieut. Maury may continue to have, 

 and more completely, the cooperation of the Navy Department in car- 

 rying out his system of investigations; and we would commend the 

 subject also to the commercial cruisers, who with little effort, might 

 contribute to the general fund, facts of great value to commerce as 

 well as science. Lieut. Maury also presents conclusions with reference 

 lo the circulation of the air, from the recent discoveries of Faraday 

 respecting the magnetic character of oxygen, and other deductions from 

 the researches of Ehrenberg on the organic life of the transported dust 

 of the atmosphere. This part of the Report contains extended citations 

 from Ehrenberg's recent work ; and in view of the occurrence of South 

 American forms of microscopic organisms in the Atlantic dust off the 

 African coast, he suggests that the dust is carried ofT by '^ the whirl- 

 winds which accompany the vernal equinox and sweep over the lifeless 

 plains of the lower Orinoco," while those of ''the autumnal equinox, 

 take up the organisms of the upper Orinoco and great Amazon basins." 

 The establishment of such a view will require farther investigation into 

 the organisms of these different regions. 



2. Practical Mineralogy^ Assaying and Minings with a description 

 of the useful minerals, and instructions for assaying and mining accord- 

 ing lo the simplest methods ; by Fkedekick Overman, Mining Engineer. 

 230 pp. 16mo. Philadelphia, 185L Lindsay and Blakiston. — There 

 is much practical information in this little work, but it is not all to be 

 relied on. We learn on the 2nd page that granite is the oldest of 

 rocks ; that it is composed of fragments of other rock or stony matter ; it is 

 pf great hardness and strength and of everlasting durability ; — on 

 the '4th page, metamorphic rock, "also called transition rock is the 

 second in age ;" " to this class belong a great variety of minerals as 

 gneiss, mica slate," &c. " Metamorphic rock often assumes the appear- 



of grtxnhe^ pudding-stone or stratified rock;" and on page 7 the 



Connecticut sandstone is ranked with the metamorphic rocks: on page 

 8 we read under the head of Volcanic Rocks, — " the rocks belonging 

 to this class are often found to be perfectly vitrified and of a glassy 

 appearance as basalt and some kinds of lava; the first is found in col- 



um 



came 



ns grouped torrether in isolated mountains or imbedded in other vol' 

 ic ?'ocA'5." We might go on in this citation of errors, but this will 



suffice. — Such a work is calculated to make error, rather than science 

 popular. " » 



3. A Chart giving an Ideal Section of the Successive Geological 

 Formations^ with an actual Geological section from the Atlantic to the 

 Pacific ocean, the whole illustrated by the characteristic fossils of each 

 formation ; by James Hall.— This geological chart by Mr. Hall is in- 

 tended for class instruction, and is well adapted for this purpose. It 



