February 18, 1887.] 



8CIEJSrCE, 



157 



«lopes of the valley on either side from the water- 

 line upwards. Their submergence is evidently, 

 "therefore, a matter of quite recent date, even histori- 

 cally speaking. 



From the above facts and traditions I reconstructed 

 the history of the formation of the cascades, the 

 •damming and backing up of the stream above, and 

 ihe consequent submergence and killing of the trees 

 which grew immediately along its bank, as follows : — 



At the time when the general cutting of the Co- 

 lumbia valley had reached abotit the level of the jores- 

 •ent flood-plain at the Cascades, through some crack 

 •or other natural opening its waters found a passage 

 into the underlying conglomerate bed, which, being 

 permeable, allowed a passage of this water down 

 stream to a point in the bed itself where it outcropped 

 at or above the level of the lower part of the 

 stream. Such a passage, once established, would be 

 Tapidly enlarged by the force of such an overlying 

 mass of water as the Columbia River; and to those 

 familiar with the corrading force of water, as shown 

 in the stream-action of western rivers, it must readi- 

 ly be apparent that it would soon become large 

 enough to take in the whole stream ; that thus for a 

 certain distance the whole Cokxmbia would run 

 underground, like the so-called 'Lost Elvers,' which 

 :are still found tinder the basalt flows of the Snake 

 Biver jjlains. Thus would have been formed the 

 natural bridge spoken of by the Indians. Moreover, 

 by this lowering of its bed at this point, the bed of 

 the river above would have been correspondingly 

 lowered, and tree-growth would have gradually ex- 

 pended down to the water's edge, as it does at pres- 

 'ent. 



Meantime the corrasion of this underground 

 stream would gradually wear away the supports of 

 the overhanging sheet of basalt, until at length they 

 became inadequate to hold it up ; and when they 

 fell, the underground passage would have been sud- 

 denly filled, the river dammed up to the present 

 level, and the stream also backed up so as to cover 

 the roots of and thereby kill the trees along the lower 

 part of its banks. Such is essentially the present 

 ■condition of the stream : for the broken masses of 

 the basalt which form the present stream-bed at the 

 Cascades resist the weariug-away of the water better 

 than did the conglomerate, and the river above the 

 Cascades still stands at a higher level than it did be- 

 fore the falling-in of the basalt bridge. 



I must admit the possibility that an actual survey 

 of the region about the Cascades might disclose facts 

 that would make the above explanation inadmissible, 

 since it is founded on a very hasty and superficial 

 examination. In spite of the fact of Captain But- 

 ton's later and possibly more thorough examination 

 than my own (for I have not been there since 1870), 

 I am not quite willing to yield my theory in favor of 

 his, for the reason that his theory involves what 

 seems to me a geological improbability, — one which, 

 in my experience at least, has not been supported by 

 ':any observed facts. This is, that an earth movement 

 — for such the flat anticlinal arch he asstimes to ac- 

 count for the raising of the old flood-plain below the 

 Cascades involves — coiild have jDroceeded more 

 rapidly than the corrasion of as large a stream as the 

 Columbia, so as to actually dam it up, and then have 

 ■conveniently stopped, so as to allow corrasion to 

 gain its former ascendency over the earth-movement. 



S. F. Emmons. 

 Washington, Feto. 8. 



A carnivorous antelope. 



A few months ago, while visiting a friend on a 

 cattle-ranch in the San Andreas Mountains of south- 

 ern New Mexica, I saw what to me seemed a most 

 abnormal habit. My friend had a young antelope six 

 or seven months old, which he had captured when 

 very j'oung, and kept as a pet about the ranch. This 

 animal is, by the way, very tame, following its mas- 

 ter about without once offering to join its fellows, 

 which often come in sight of the house. When 

 offered jjieces of raw beef, it will eat the meat with 

 evident relish, and in preference to vegetable food. 

 I have seen it eat piece after piece until it has dis- 

 posed of half a pound or more, then it would walk to 

 the corn-crib and eat corn as a sort of dessert. It 

 also eats bread, cooked potato, and sweet-potato 

 both raw and cooked. Ralph S. Taee. 



Cambridge, Feb. 14. 



Language-teaching. 



The important subject of the teaching of modern 

 languages having been disciissed in the columns of 

 Science., and no definite plans having been offered by 

 either of the writers discussing it, perhaps the origi- 

 nal and independent views of a practical teacher will 

 not be unwelcome. 



It is obvious that a complete knowledge of a lan- 

 guage consists, 1°, in having full command over the 

 bodily organs through which it is either received or 

 communicated to others, — viz, the vocal organs, 

 ears, and eyes, — so as to be able to utter any sound 

 like a native, to understand all that he says, and to 

 read any book aloud in the proper manner ; 2°, in 

 mastering those fundamental rules of grammar — in- 

 cluding those of the verbs — indispensable in order 

 to speak and write correctly ; 3°, in the possession of 

 a fund of words and idiomatic forms for the expres- 

 sion of ideas; and, 4*^, in the power of using these 

 words and forms according to the special genius of 

 the language studied. 



Sounds of the human voice are the vibrations of 

 an expired current of air, produced by the vocal 

 organs, which (in the case of the French pronuncia- 

 tion) are, for the formation of every sound, in a fixed 

 and determined position. In my book on pronunci- 

 ation, ' French orthoepy,' I have indicated the rela- 

 tive positions of the vocal muscles for every French 

 articulation and vowel. The learner is trained, by 

 means of different vocal exercises, to use the instru- 

 ment of speech in exactly the same manner as the 

 natives ; and, employing the same means, he must 

 necessarily obtain the same result. These gymnas- 

 tics of the voice are accomplished in a few short 

 hours, and are an indispensable preliminary exer- 

 cise before commencing the study proper of the 

 language. 



Teaching a language without the few fundamental 

 rules that regulate it, including those of the verbs, is 

 depriving the student of a most valuable aid and 

 guide ; while making grammar the all-important sub- 

 ject, esj)ecially in the beginning, is to create a con- 

 fusion in his mind, and to impede his progress.' I 

 have taken a middle course; and in my grammar will 

 be found, in a concise form, only those general rules 

 without which nobody can either speak or write 

 properly. My grammatical exercises have been 

 framed with the view of initiating the learner into 

 the idioms and construction of the language. To 

 avoid those disconnected and commoni^lace phrases 



