Morning journal and courier., 1883-11-17
Depreaaions and Kett1e Ho1es.

The Terrace Formation of the New Ha-I
 ven Valley Treated by Professor Dana
 Other Papers Read Before the Nation
 al Academy of Sciences Kesterday-The
 Death Roll.
 Professor J. D. Dana gave on the platform in the lecture room of North Sheffield Hall yesterday afternoon the information in re rard to the terrace formation or stratifed drift and the kettle holes and deserted river channels of the New Haven valley which he described to those of the scientists who ac- oompanied him about the region last Wednes- day. His paper possessed more information of local interest than any other which was read before the academy. He said that the New Haven plain was broad and flat with an svenness of grade which was only produced under water. Evidences of justification show that immense bodies of running water once passed over the region. A peculiar fea- ture of the formation is the terrace founda- tion which with remarkably even grades reaches the hills. In this plain there are two large deHressions that are difficult to account for. One is the Beaver pond depression, the other the Pine Marsh creek. They are very similar and present 8 sudden fall from the surrounding country of from 20 to 40 feet. Water is abundant in these Impressions, but is obtained by subterranean channels. There is quite 8 breadth to the Impressions, from
 
 great river. The bottom of the Beaver ponds depression is 25 feet below the sea level and in places where soundings have been made depth of 52 feet has been reached. The de- pressions must therefore have been e1cavated ia some way below sea level. How could this have been accomplished2
 In the glacial period Mill river was great stream rising far to the north of us and car rying down immense quantities of water. Such streams would naturally take the short est course to the sea and the route by Fine Marsh creek and Beaver ponds from Mill river is that which would naturally have been taken. Undoubtedly there was at point below CenterviIle such 8 branch in the stream. The depth alluded to shows that the channels are glacial channels formed by the natural glacial discharge. The deposits or sand and gravel borne down by these vast streams would naturally clog the shallowest portions and the whole region bears evidence of being made up in this way. It was made rather to the west than the east by the lnhu- ence of the earth's rotation. The two great depressions alluded to were undoubtedly made in this way.
 The kettle holes in the plain clustered about these depressions are more puzzling objects of study. There are thirty of these about Pine Marsh creek and nearly as many about Beaver ponds They are quite large, resembling large bowls. They are deep and run down to water very often. To account for these there are more or less theories advanced The one which seems most reasonable, while not be- ing entirely satisfactory perhaps, considers them as being places alongside of the main stream where there are deep holes, deposits were made around them gradually, there be- ing perhaps some whirl in the water which would keep then open. At any rate they were made at the same time as the other depressions Another spot of kettle holes int hd even more difficult to account for, not being near any great depression. There IS small stream running into Mill river there. A dam was once formed by ice across the gap at Mt Carmel which ran the water up to 169 feet. This dam is proved to exist by deposits along | the narrow pass. Af the west angle the | stream flowed of from the dam in a channel beautifully cut out by the stream. Large stones are along the course, but none of them are at all scratched, showing thai l only by the stream the channel was cut Ii | is Q natural course for stream snch that the | railroad company has moved it's track to that valley. That plunging stream made deer 1 channel there, and the waters sfterward d1o
 not fill the depths with sand and gravel depo sition.
 Prof. Newberry said he was much puzzled | by the topographica features described by
 Prof Dana. He was familiar with the kettle l holes in the Vest but there they are not I SANAGA-S SS~~~S~- - | and the kettle holes should be made in order
 to fully settle the matter. | Other papers read before the academy were
 notes on the minerology and lithology of the Bodie mining district of California by Prof
 Silliman; marriage institutions in tribal so.
 ciety; personality in the measures of Venus
 diameter as derived during transit acrossthe
 sun, by O. T. Sherman; the reductions of
 barometric observations to sea-leVel, by Prof
 Elias Loomis; the afinities of the Dinosau-
 rian reptiles, by Prof. Marsh the ancient
 Placiation of North America, by Prof. J. s.
 Newberry.
 Prof. Marsh announced that in accordance
 with the United States law the next meeting
 of the academy would be held at Washington
 next April. The death list was announced aE follows: Prof. Alexander of Princeton,
 June 25 Prof. Wm. A. Norton of Yale
 September 21; Prof. J. Lawrence Smith oi
 Louisville, October 12 and MT. John L.
 LeCompte of Philadelphia, Nov. 15. Prof.
 Young, of Princeton, will prepare an obit
 uary memoir Of Prof. Alexander, Prof | Trowbridge of Columbia on Prof. Norton Prof. Silliman of Yale on Prof. Smith. A
 vote of thanks was extended to the govern
 ing board of the Scientific school for theiI
 kindness to the academy.