274 



SCIENCE. 



[Vol. XIX. No 484 



it at any other point; for his relation to our space is nearly 

 the same as our relation to a plane. If ghosts are four-fold 

 beings, the erratic nature of their movements may become 

 more comprehensible in the course of time. An ordinary 

 knot could in four-fold space be readily untied by carrying 

 one loop out of our space and bringing it back in a different 

 place. In fact, a knot in our space would be simply a loop 

 or coil in four-fold space. A flexible closed shell could be 

 turned inside out as easily as a thin hoop can with us; and 

 many other apparent impossibilities become mere child's 

 play. But the realization of four-fold space cannot be 

 learned by giving attention to such liUle curiosities as these. 

 Only a systematic and continued study of the figures and 

 motions of higher space can be expected to give results of 



educational value. And when (or, if) our conception of 

 four-fold space becomes clear, we shall be reaciy to recognize 

 the existences and motions of the fourth dimension if there 

 be such. 



THE TUSKALOOSA FORMATION. 



Professor Lester F. Ward has recently spent a couple of 

 weeks in Alabama in making a study of the Tuscaloosa for- 

 mation, both as to its stratigraphy and its fossil plants. While 

 in Alabama the professor made Tuscaloosa his headquarters, 

 and from there made a number of short excursions in com- 

 pany with Dr. Eugene A. Smith to places of interest. At 

 Cottondale, some eight miles east of Tuscaloosa, there is a 

 fine locality for the collection of fossils, chiefly well-pre- 

 served leaf impressions. Professor W. M. Fontaine, a number 

 of years ago, spent some time here and collected a great 

 number of these leaves, which are now in the hands of Pro- 

 fessor Ward for study and description. 



Between Cottondale and Woodstock there are many occur- 

 rences of the Tuscaloosa sands and clays, which are now only 

 outlying remnants, upon the rocks of the Coal Measures, of 

 what was once probably a continuous mantle. Although 

 there are many places where excellent clays for economic 

 purposes are to be seen, none of them thus far examined 

 have been found to contain the leaf impressions. From 

 their position, these beds, occurring between Cottondale and 

 Woodstock, appear to be the oldest of the Tuscaloosa series, 

 and the leaf-bearing beds thus appear to be tolerably well up 

 in the formation, although wherever seen, at Cottondale, 

 Tuscaloosa, Snow's, Shirley's Mill, Glen Allen, etc., the 

 leaf-bearing clays rest directly and unconformably upon the 



Coal Meas ures, usually within thirty or forty feet of the lin 

 of contact of the two formations. 



The other localities mentioned above, except Glen Allen, 

 being away from the railroad lines, had to be reached by 

 private conveyance. 



Snow's, about seven or eight miles west of Tuscaloosa, was 

 first examined by Dr. Smith seme years ago, and Professor 

 Fontaine made a large collection here also. In the gullies 

 near Snow's there is fine opportunity for seeing the strata of 

 the Tuscaloosa formation, in vertical section. One of these is 

 more than one hundred feet deep. Shirley's Mill, eleven miles 

 south-east of Fayette Court House, was first made known as 

 a plant-bearing locality by Dr. George Little, who visited it 

 last year while making an examination of the Tuscaloosa 

 clays, for the Geological Survey of the State. Dr. Little 

 brought back a few fine leaf impressions from here, but Pro- 

 fessor Ward was the first to make a systematic collection of 

 the fossil plants. Glen Allen, on the Kansas City, Mem- 

 phis, and Birmingham Railroad, was first examined and a 

 small collection made by Dr. Smith several years ago, but 

 here again Professor Ward was the first to collect on a large 

 scale. The leaves are in a dark colored clay that at certain 

 stages of wetness is tough and intractable, but when prop- 

 erly dry yields beautiful specimens at every stroke of the 

 hammer. The same is true of the clays near Shirley's Mill, 

 and at both these places one can in a few hours load a wagon 

 with fine cabinet specimens. 



The Tuscaloosa formation is now generally considered a 

 member of the lower Cretaceous, in part at least equivalent 

 to the Potomac of McGee. While the fossils have not yet 

 been sufficiently studied to decide their exact equivalence, 

 many of the leaves appear to be identical with those occur- 

 ring in the Amboy clays of New Jersey. 



While in Tuscaloosa Professor Ward had an opportunity 

 also of collecting some rare living plants. Upon the banks 

 of the Warrior River, a few miles above the town, under 

 the guidance of Drs. Bondurand and Hall, he was able to 

 obtain Neviusia Alabamensis, SedumNevii, Croomia pauci- 

 flora, all comparatively rare, the first named having been 

 found only in this locality. In Dr. Smith's yard is growing 

 the Croton Alabamensis, recently discovered on the banks 

 of the Cahaba River, and of interest as being the only 

 shrubby Croton in our North American flora. This one 

 grows to the height of eight or ten feet and makes almost 

 impenetrable thickets. When slightly bruised the leaves 

 and stems give out a fragrance somewhat like that of the 

 flowers of the crab-apple. 



An excursion was also made by Dr. Smith and Professor 

 Wai'd to a little village, Havana, some twenty-five miles 

 south of Tuscaloosa, long known to the former as an inter- 

 esting locality, where, in a rocky glen under overhanging 

 cliffs, grow two rare ferns, Asplenium ebenoides and 

 Trichomanes radicans. The former has been noted from 

 only three other localities, all in different States of the 

 Union. Near Havana there are some great gullies, locally 

 known as " The Caves," in which the micaceous sands of the 

 uppermost of the Tuscaloosa formation are laid bare. These 

 sands are remarkable for their brilliant colors, red, pink, 

 purple, and yellow. In this respect they called to mind the 

 similar bright hues of Gay Head in Massachusetts. 



E. A. S. 



Me. W. J. HussEY of the Ann Arbor Observatory has re- 

 ceived an appointment as astronomer at the Leland Stanford, Jr., 

 University. 



