582 



NATURE 



[April 1 8, 1889 



Possibly some of your readers may have considered this 

 problem, and may be able to suggest some other method of 

 packing the spheres. I do not remember to have met with 

 any discussion of it. W. Steadman Alois. 



University College, Auckland, New Zealand, February 4 



Temperatures in Lake Huron. 



Some very interesting results observed by Commander Boulton, 

 R.N., on the temperature of the waters of the Georgian Bay, 

 the eastern basin of Lake Huron, have been placed by him in 

 my hands. They appear to establish that the waters of the 

 bottom of the bay are colder than the even deeper waters of the 

 rest of the lake. 



Lake Huron in its profound depths forms three great basins — 

 the Georgian Bay, defined along its western outline by the bold 

 cliffs of the Niagara limestones, and the central and southern 

 basins, separated by the subaqueous corniferous escarpment which 

 diagonally crosses the lake in a south-eastern direction from the 

 outline of Lake Michigan. Whilst the southern basin has 

 generally a sandy bottom, and is in many parts comparatively 

 shallow, the central basin has a floor chiefly of clay, and includes 

 the deepest portions of the lake. 



The surface temperature necessarily varies with the seasons, 

 and with the continuous or fitful nature of the weather for days 

 preceding the observations. Thus on May 11, 1888, when the 

 ice had but recently broken up, the surface water of the Georgian 

 Bay near Owen Sound registered 34° F., whilst at 154 fathoms 

 the minimum was 34^° F. 



Observations will during the coming summer be continued in 

 this and other lakes, but in the meantime the records given here- 

 under may be taken as preliminary illustrations of the tempera- 

 ture of the waters of the bay. For comparison, some published 

 observations taken in i860 by the United States engineers in the 

 central and southern basins are also given. 



Georgian Bay, 

 Lat. 45° 6', Jong. 81° 7 



July 27, r ■ ■ 



Surface 

 10 fathoms 

 20 ,, 



35 

 66 



1, 8.30 a.m. 

 OF. 

 6oi 



(bottom) 



45f 



41 



39i 



Central Basin. 



Lat. 45° 18', lottg. 82° 23'. 



July 30, 8 a.m. 



Surface 52 



65 fathoms (bottom) 42 



Southern Basin. 

 Lai. 44* 33', long. 82° 54'. 



August 5, 10 a.7n. 



OF. 



Surface 58 



38 fathoms (bottom) 52 



Lat. 43° 46', long. 82° i'. 

 yune 20, 9 a.m. 



Surface 



45 fathoms (bottom) 



J-at. 45° 35', long. 80° 49'. 

 August 20, 1886, 8 a.m. 

 OF. 



Surface 593 



31 fathoms (bottom) 39^ 



Lat. 45°, lo7tg. 80° 52'. 

 August 20, 1886, 12.38 /.w. 

 o F. 



Surface 65 



42 fathoms (bottom) 37I 



On August 20, 1886, the temperature of the surface rose from 

 S9| F. at 8 a.m., to 62° at 9 a.m., 63!° at 11.34 a.m., and 65° 

 at 12.38 p.m. 



The suggestive explanation of the lower temperature of the 

 Georgian Bay depths is that whilst "the more southern and 

 warmer waters of Lake Michigan in their course from the inlet 

 to the outlet do not reach the bay, a considerable portion of the 

 colder waters of Lake Superior find their way into it by the 

 channel north of the Manitonlin Islands. Further, the sub- 

 aqueous cliffs which block the western side of the bay preclude 

 a free circulation between the deeper waters of the bay and the 

 profound depths of the lake beyond. A. T. Drummond 



Will Fluctuations in the Volume of the Sea account for 

 Horizontal Marine Beds at High Levels ? 

 In the interesting article "On the Gradual Rise of the Land 

 m Sweden" (Nature, March 21, pp. 488-92), Nordenskiold 

 arrives at the conclusion that the small alterations of the relative 

 level of sea and land which observation proves have taken place 

 in Sweden, are due to movements of the land, not to fluctuations 

 of the sea-level. On the other hand, he contends that the extensive 

 horizontal stretches of marine strata found in many places on the 



earth's surface at heights measured by thousands of feet above : 

 sea-level indicate fluctuations of level in the sea itself. Thi 

 certainly reversing the order of things as believed in by m 

 geologists. It is also suggested that the fluctuations of sea-levc, 

 are due to alternate increase and decrease of the volume of the) 

 sea, arising from gaseous and fluid additions from outer space ori 

 loss thereto, the alternate gains and losses balancing one anothci' 

 over long periods. 



It is not my object in this communication to discuss the 

 physical possibility of such alterations of the volume of the sea^ 

 having taken place in this way, but to point out that, even ifj 

 granted, such rising and falling of the sealevel fails to explain' 

 the geological phenomena for which it is invoked. Formatioi 

 horizontal in one place are disturbed in another. They cam 

 be divided into two hard and fast stratigraphically dissimilarkin 

 of marine deposits, ihe horizontal d^nd th& folded, as is attempte 1 

 by Nordenskiold. Even the example quoted by him of the 

 Tertiary strata of Spitzbergen shows this, as it is stated, "Near 

 the west coast they are much disturbed, but further inland they 

 form horizontal strata of sand and clay, &c." 



The plains of Russia are, as was shown long ago by Murchison, 

 largely occupied by nearly horizontal strata of undisturbed 

 Silurians, while in the Ural Mountains the same formation is 

 thrown up on end. I venture to pronounce this continuity of 

 horizontal with disturbed deposits an almost universal pheno- 

 menon, for where plateaus are capped by horizontal strata, 

 as often happens, these cappings are only the remnants left l>v 

 denudation. 



It is a well-known geological fact that as strata recede fron, 

 mountain range they become less and less disturbed and mu.. 

 horizontal. Again, there are no horizontal strata of any extent 

 or thickness that are not riven with faults showing that they 

 have been subjected to upthrow or downthrow as the case may 

 be, and these have to be accounted for as well as the level at 

 which the strata occur. Except in the very newest deposits, 

 strata bear very little relation to the levels at which they are 

 now found. Because strata are often horizontal at high levels 

 it is no indication that they have not been upheaved. The 

 Colorado plateaus may be cited as an instance, and sucli 

 instances may be multiplied to any extent. 



There is, however, another difficulty appertaining to the ex- 

 planation offered by Nordenskiold. It is this, the general rise if 

 the sea-level over the whole globe to the extent even of 1000 feet 

 would obliterate an enormous area of land. Where, then, would 

 the sediment come from to form the beds appealed to in proof of 

 the rise of the sea-level ? Formations are not arranged concen- 

 trically at varying levels or, in other words, stratigraphically 

 contoured, as would be the case were they due to this cause. But 

 there is a final and still greater difficulty to be met. Denudatio!i 

 is year by year reducing the height of the land, and if no com- 

 pensatory elevation excepting over disturbed areas took place, 

 continents instead of growing as they are supposed by some to 

 do, would long ago have been obliterated, and the earth plane I 

 dov/n to a uniform level, so that when periods of "hi; 

 water" recurred all terrestrial life would be destroyed. 11; 

 contingency no doubt to some minds will be plain demonstrati. 

 of the truth of Nordenskiold's theory. 



T. Mellard Reade. 



Park Corner, Blundellsands, near Liverpool, March 25. 



The Meteorological Conditions of the Aruwhimi Forest 

 Tract. 



I CANNOT but think that the true explanation of the rani: 

 exuberance of the Aruwhimi forests, so graphically descrior 

 by Mr. Stanley, or rather of the humid climate that fotc: 

 them, is different from that suggested either by the gn 

 traveller himself or the writer of the notice in last weel; 

 Nature. The source of the winds that feed the rainfall > 

 this region seems to me a question of secondary importanc 

 but since in equatorial regions, as a rule, easterly winds pr^ 

 dominate, I am inclined to think, -with the wiiter of the arlicl 

 that this source is most probably the Indian Ocean, 



If, however, this be so, since in the interval between th 

 coast and the Aruwhimi basin they have to pass over some ^ 

 the highest mountains in the continent, and reach the latter ( ■ 

 a descending slope, they would be comparatively dry win l~ 

 more or less analogous to the A\pmefdhn, were there not oth 

 conditions present which more than counterbdmce the desicca 

 ing influence of the eastern mountains. The first and me 



