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the gas.

the very best intentions in the matter. The difficult to explain the small residue, befacts were too much for us; and all we can cause in the manipulation of the gases do now is to apologise for ourselves and for large quantities of water are used; and, as

I have already explained, water dissolves Several questions may be asked, upon argon somewhat freely. In the processes which I should like to say a word or two, of manipulation some of the argon will if

you will allow me to detain you a little come out of solution, and it remains after longer. The first question (I do not know all the nitrogen has been consumed. whether I need ask it) is, have we got hold Another wholly distinct argument is of a new gas at all? I had thought that founded upon the method of diffusion inthat might be passed over, but only this troduced by Graham. Graham showed morning I read in a technical journal the that if you pass gas along porous tubes you suggestion that argon was our old friend alter the composition, if the gas is a mixnitrous oxide. Nitrous oxide has roughly ture. The lighter constituents go more the density of argon ; but that, as far as I readily through the pores than do the can see, is the only point of resemblance be- heavier ones. The experiment takes this tween them.

form. A number of tobacco pipes—eight Well, supposing that there is a new gas, in the actual arrangement-are joined towhich I will not stop to discuss, because I gether in series with india rubber junctions, think the spectrum alone would be enough to and they are put in a space in which a prove it, the next question that may be asked vacuum can be made, so that the space outis, is it in the atmosphere? This matter side the porous pipes is vacuous or approxinaturally engaged our earnest attention at mately so. Through the pipes ordinary an early stage of the enquiry. I will only air is led. One end may be regarded as indicate in a few words the arguments open to the atmosphere. The other end is which seem to us to show that the answer connected with an aspirator so arranged must be in the affirmative.

that the gas collected is only some 2 per In the first place, if argon be not in the cent. of that which leaks through the porosatmosphere, the original discrepancy of ities. The case is like that of an Australian densities which formed the starting point river drying up almost to nothing in the of the investigation remains unexplained, course of its flow. Well, if we treat air in and the discovery of the new gas has been that way, collecting only the small residue made upon a false clue. Passing over that, which is less willing than the remainder to we have the evidence from the blank exper- penetrate the porous walls, and then prepare iments, in which nitrogen originally derived nitrogen' from it by removal of oxygen from chemical sources is treated either with and moisture, we obtain a gas heavier than oxygen or with magnesium, exactly as at atmospheric nitrogen, a result which proves mospheric nitrogen is treated. If we use that the ordinary nitrogen of the atmosphere atmospheric nitrogen we get a certain pro- is not a simple body, but is capable of being portion of argon, about 1 per cent. If we divided into parts by so simple an agent as treat chemical nitrogen in the same way

the tobacco pipe. we get, I will not say absolutely nothing, If it be admitted that the gas is in the but a mere fraction of what we should get atmosphere, the further question arises as had atmospheric nitrogen been the subject. to its nature. You may ask, why do we get any fraction At this point I would wish to say a word at all from chemical nitrogen? It is not of explanation. Neither in our original announcement at Oxford, nor at any time There seems to be a great discrepancy of since, until the 31st of January, did we opinions. Some high authorities, among utter a word suggesting that argon was whom must be included, I see, the celean element; and it was only after the ex- brated Mendeleef, consider that N, would periments upon the specific heats that we be an exceptionally stable body; but most thought that we had sufficient to go upon of the chemists with whom I have consulted in order to make any such suggestion in are of opinion that Ng would be explosive, public. I will not insist that that observa- or, at any rate, absolutely unstable. That tion is absolutely conclusive.

It is cer

is a question which may be left for the tainly strong evidence. But the subject is future to decide. We must not attempt to difficult, and one that has given rise to some put these matters too positively. The difference of opinion among physicists. balance of evidence still seems to be against At any rate, this property distinguishes the supposition that argon is N3, but for argon very sharply from all the ordinary my part I do not wish to dogmatise. gases.

A few weeks ago we had an eloquent One question which occurred to us at the lecture from Professor Rücker on the life earliest stage of the enquiry, as soon as we and work of the illustrious Helmholtz, It knew that the density was not very differ- will be known to many that during the last ent from 21, was the question of whether, few months of his life Helmholtz lay prospossibly, argon could be a more condensed trate in a semi-paralyzed condition, forgetform of nitrogen, denoted chemically by the ful of many things, but still retaining a symbol Ng. There seem to be several diffi- keen interest in science. Some little while culties in the way of this supposition. after his death we had a letter from his Would such a constitution be consistent widow, in which she described how interwith the ratio of specific heats (1.65) ? ested he had been in our preliminary anThat seems extremely doubtful. Another nouncement at Oxford upon this subject, question is, Can the density be really as and how he desired the account of it to be high as 21, the number required on the sup- read to him over again. He added the position of N,? As to this matter, Professor remark: “I always thought that there Ramsay has repeated his measurements of must be something more in the atmosphere." density, and he finds that he cannot get even so high as 20. To suppose that the

LLOYD MORGAN UPON INSTINCT. density of argon is really 21, and that it In the last number of Natural Science appears to be 20 in consequence of nitrogen Professor C. Lloyd Morgan gives a valuable still mixed with it, would be to suppose a synopsis of the various definitions of incontamination with nitrogen out of all stinct which have been proposed by Darproportion to what is probable. It would win, Wallace, Romanes, James, Spencer mean some 14 per cent. of nitrogen, whereas and other writers upon this subject. He it seems that from one-and-a-half to two shows that surprisingly wide differences of per cent. is easily enough detected by the opinion prevail and concludes that, “Since spectroscope. Another question that may be the question of origin is still sub judice, the asked is, Would Ng require so much cool- definition should be purely descriptive, so ing to condense it as argon requires ? as not to prejudge this question. And

There is one other matter on which I since the phenomena of instinct can only would like to say a word—the question as be rightly understood in their relation to to what Ng would be like if we had it. automatism connate and acquired, to impulse, to imitation and to intelligence, our Random Movements : Congenital, more or definition of instinctive activities should less definite, but not specially adaptive find a place in a scheme of terminology." movements of limbs or parts of the body ; He sets forth such a scheme sending us in either centrally initiated or evoked by MSS. a number of additions and modifi- stimuli. cations which are embodied in the follow- Instinctive Activities : Congenital, adaptive ing table and abstract:

and coördinated activities of the organism “It may be premised:

as a whole; specific in character, but sub1. That the terms congenital and acquired ject to variation analogous to that found in are to be regarded as mutually exclusive. organic structures ; similarly performed by What is congenital is, as prior to individ- all the members of the same more or less reual experience, not acquired. What is ac- stricted group, in adaptation to special cirquired is, as the result of individual experi- cumstances frequently recurring or essenence, not congenital.

tial to the continuance of the race; often 2. That these terms apply to the indi- periodic in development and serial in charvidual, whether what is acquired by one acter. individual may become congenital through Mimetic Movements and Activities : Due to inheritance in another individual, is a ques- individual imitation or similar movements tion of fact which is not to be settled by or activities performed by others. implications of terminology.

Impulse (Trieb): The affective or emotional 3. That the term acquired does not ex- condition, connate or acquired, under the clude an inherited potentiality of acquisi- influence of which a conscious organism is tion under the appropriate conditions, prompted to movement or activity, without such inherited potentiality may be termed reference to a conceived end or ideal. innate. What is acquired is a specialization Instinct: The congenital psychological imof a vague and general innate potentiality. pulse concerned in instinctive activities.

4. That what is congenital and innate is Control : The conscious inhibition or auginherent in the germ plasm of the fertilized mentation of movement or activity. oyum.

Intelligent Activities : Those due to indiviCongenital Movements and Activities : Those dual control or guidance in the light of exthe performance of which is antecedent to perience through association. individual experience; they may be per- Motive: The affective or emotional condiformed either (a) at or very shortly after tion under the influence of which a rational birth connate) or (b) when the organism being is guided in the performance of dehas undergone further development (de- liberate acts. ferred).

Deliberate Acts: Those performed in disCongenital Automatism: The congenital tinct reference to a conceived end or ideal. physiological basis of those movements or Habits : Organized groups of activities, activities which are antecedent to individ- stereotyped by repetition, and characteristic ual experience.

of a conscious organism at any particular Physiological Rhythms : Congenital (or con- stage of its existence. nate) rhythmic movements essential to the Acquired Movements, Activities or Acts: Those continuance of organic life.

the performance of which is the result of Reflex Movements : Congenital, adaptive individual experience. Any modifications and coördinated responses of limbs or parts of congenital activities which result from of the body ; evoked by stimuli.

experience are so far acquired.

Acquired Automatism : The individually broken by hills, which rise 200 to 300 feet modified physiological basis of the perfor- above the general level. The highest of mance of acquired movements or activities these are capped by the hard Niagara limewhich have been stereotyped by repetition.' stone; the lower by beds of the Cincin

Professor Morgan points out that there is nati group. These hills form the so-called some overlap in these definitions, but it is ‘mounds,' of which, in the area visited, the difficult to see how such overlaps are to be Platte Mounds—1250–1300 feet, A. T.-are avoided.

H. F. 0. the highest. The hard Niagara limestone

caps of these mounds are the remnants of SOME MEANDERING RIVERS OF WISCONSIN.

beds which formerly stretched over all this Two years ago Professor Davis* called region, and which has since been removed attention to the wide meanders of the Osage by denudation. To hills of this type Prof. river of Missouri. He said:

" The me

Davis has given the name, Monadnocks. anders of the river are peculiar in not being The rocks of this region are nearly horilike those of the Mississippi, spread upon a zontal, and in general there is not a sharp flat flood-plain. High spurs of the upland contrast between the slant of the beds and occupy the neck of land between

every

turn the general slope of the upland surface. It of the stream. Evidently the meanders are seems, therefore, as if the upland might be not of the ordinary kind.” He explained a structural plain due to a resistant stratum, the peculiar tortuous course of the river as the Galena limestone, at the level of the an inheritance from an earlier cycle, during upland—a stratum which had been revealed which the river had worn the land down to by denudation of the overlying beds. If a surface of faint relief. The stream at this were the case, the upland level would that time swung to and fro in broad me- be independent of any former baselevel. anders developed on a wide flood-plain. But such a conclusion does not seem to be The whole region was then somewhat ele- admissible; although nearly horizontal, the vated, and the stream again set to work to limestone has been bent into gentle flescut down its channel to the new baselevel.

ures, some of which are sufficient to bring But the meandering course which it had the underlying Trenton limestone and St. acquired late in the preceding cycle was Peter's sandstone up to the level of the carried over into the new cycle of its life. upland surface. The plain is continuous

A recent visit to a part of the driftless across these low arches and bevels the area of Wisconsin, Lafayette and Grant edges of the gently inclined beds. counties, gave me an opportunity of ob- over, to the north of the outcrop of the serving a similar habit of some of the Galena limestone, the upland plain bevels rivers of that region. The general surface the gently inclined edges of the underlying of the country is that of a gently rolling formation, which there come to the surface. plain, at an elevation of from 850 to 1000 In that region, however, the plain is now feet, A. T. The interstream surfaces are more completely dissected than further broad and slightly undulating, but well south. Whatever correspondence exists drained. The surface rock, except in the between the inclination of the beds and the immediate vicinity of the streams, is the slope of the plain is fortuitous and not due Galena limestone. Occasionally the gen- to structure primarily. It is believed that eral level of the top of the country is this plain is a surface of denudation, the *SCIENCE, April 28, 1893, vol. xxi., p. 225 et seq.

result of long continued erosion on SCIENCE, November 17, 1893, vol. xxii., p. 276 et seq. greater land mass when the land stood lower

than at present. The upland surface is be- ence in the slope of the valley sides and the lieved to be an elevated peneplain.

upland plain indicates a change of level It is now moderately dissected by valleys before the excavation of the valleys and which along the larger rivers are from 100 after the formation of the upland plain. to 200 feet deep. In comparison with the The process by which the valleys are being width of the gently undulating interstream formed is not a direct continuation of the surfaces these valleys are not very wide. process by which the gentle upland slopes The slopes are quite steep and locally form were fashioned. The valleys were cut in bluffs, but towards the top they pass by a the upland surface after it was elevated graceful curve into the almost level upland. from the low position which it had during The present flood-plains along the bottoms its formation. of the valleys are generally from an eighth Confirmatory evidence for this hypothto a quarter of a mile in width. In terms esis is found in the winding courses of of development the present valleys are well the valleys which now dissect this upland. on towards maturity. The sharp narrow Fever river was studied in the field, and valleys of extreme youth are entirely ab- the topographical atlas of the Wisconsin sent. The rivers have made considerable Geological Survey shows that the Platte, progress in the present cycle in reducing the Little Platte, Grant and Pecatonica rivers land mass to the level dependent on the have this same habit. If the geographical grade of their channels, but the amount of development of this region was as outlined work still to be done is vastly in excess of above, the streams at the close of the what has already been accomplished. earlier cycle must have possessed wide, flat

The three topographic features mentioned, valleys, with broad flood-plains, in which namely, the broad undulating upland, with they meandered freely. The elevation of an elevation of from 850 to 1,000 feet; the land would have caused the streams to the few monadnocks rising above it, and degrade their channels rapidly. In many the valleys cut into it, give a clue to the cases the meanders on the flood-plain stages of geographic development of this would have been superimposed upon the region. The upland peneplain is a surface of rock below, as the river bed was lowered. denudation produced by long continued The valleys cut in the elevated peneplain erosion, when the land mass stood lower would thus come to preserve, and, than at present. This cycle of erosion pointed out by Winslow, also increase the lasted a long time and the baseleveling was meanders of the earlier cycle. almost completed. Very few monadnocks Such seems to have been the case with rose above the general plain. The cycle the Fever river. Its meanders have an was ended by an uplift, which quickened average radius of a little less than half a the streams, restored to them their cutting mile, but they are by no means constant. powers, and compelled them to erode new Rock spurs of the upland project into each valleys in the old peneplain. They have

The slopes on these spurs are gennow cut down their channels until their erally gentler than on the outside of the ability to transport material is just about curves, where the stream is often undercutequal to the material which they have to ting the base of the slope and increasing carry. Rivers, the profiles of whose stream- the meanders. Both open and close oxchannels are in this condition of equilib m, bows occur.

The most marked of the close have been called by Davis (SCIENCE, N. S., type of meanders was noted near Benton, Vol. I., p. 176) graded rivers. The differ- where the river makes an almost closed sig

as

curve.

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