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on the part of his friends and himself could have induced him to write this letter, from which I take the following extracts:

"The middle classes are suffering frightfully in the present depreciation of money. Our salaries (which are for the present being paid) seem high according to the figures, but they are insufficient for the purchase of even the ordinary necessities of life. We may, for instance, possibly once a week have a bit of meat, but for the rest of the time we have to rejoice if we can get enough bad bread and vegetables to appease hunger. Sugar is enormously dear and never to be had in sufficient quantities. Clothing we can not buy, for a single simple suit would cost more than a month's salary. It is the same with underclothes and shoes. What our present conditions will lead to in the near future it is impossible to conceive."

... "You can imagine it is in the highest degree painful for me to write you such a letter, and only real suffering would justify it."

"While we are suffering in Austria from actual need of food, packages of food sent by individuals in America rarely reach their destination. Money is practically of no value, for there is little food to be purchased with it."

Professor whose name I withhold, writes that the American Relief Administration (whose office in this country is at 115 Broadway, New York), has established an American food warehouse in Vienna, from which food is distributed that has been shipped from this country.

JAS. LEWIS HOWE WASHINGTON AND LEE UNIVERSITY, LEXINGTON, VIRGINIA

JOURNALS FOR PRAGUE

TO THE EDITOR OF SCIENCE: Dr. M. Kojima, surgeon-commander, Japanese Navy, has but now arrived from Tchecho-Slovak where he visited Professor A. Biedl. The latter has sent through him a message to American scientists asking if they can arrange to have sent to him the various scientific publications

and periodicals, since he is unable to purchase the same on account of the rate of exchange, lack of funds, and general disturbed conditions in Tchecho-Slovak. It seems to me that the least we can do is to arrange through our editing boards some procedure by which Dr. Biedl may receive current numbers of our scientific periodicals. I would appreciate greatly your giving this communication publicity in "SCIENCE." Dr. Biedl's address is Das Institute fur Experimentelle Pathologie, Prag, Tchecho-Slovak. FREDERICK S. HAMMETT

NOTES ON METEOROLOGY

THE SUPPOSED RECURRENT IRREGULARITIES IN THE ANNUAL MARCH OF TEMPERATURE

"The belief that periods of unseasonable heat and cold tend to recur at or about the same time from year to year has prevailed over a great part of the world for many centuries and has been the subject of extensive scientific investigation." This is the opening sentence in an extensive, scholarly discussion of the "Literature concerning supposed recurrent irregularities in the annual March of temperature," by C. Fitzhugh Talman, librarian of the Weather Bureau.

Most of the literature deals with a cold period in May.

Over a considerable part of continental Europe it has been popularly believed since the Middle Ages that destructive frosts were likely to occur at a certain period in the month of May, and with the elaboration of the ecclesiastical calendar these frosts became definitely associated with the days dedicated to Saints Mamertus, Pancras and Servatius (May 11, 12, 13), or, in south-central Europe, Saints Pancras, Servatius and Boniface (May 12, 13, 14), hence known as the "ice saints." With the construction of synoptic weather charts, the barometric conditions that accompany depressions of temperature gradually became apparent.. [This cold period] was found to occur when, owing to the rapid warming of the land regions as compared with the ocean, a center of low barometric pressure develops over southeastern Europe while high pressure prevails over the ocean

...

6 Monthly Weather Review, August, 1919, Vol. 47, pp. 555-565.

to the northwest, a situation that gives rise to cold northerly and northeasterly winds in central Europe. . . . While the immediate causes of these interruptions of temperature has thus been made clear, it is not yet certain whether or to what extent such interruptions, with their attendant barometric conditions tend to recur from year to year on certain dates, such as the days of the ice saints. Irregularities in a curve showing the mean annual march of temperature as deduced from a record of 50 or 100 years may be due to excessive departures in particular years rather than to a real tendency to recurrence on particular dates, and, on the other hand, a tendency to recurrence might not manifest itself in the mean curve, especially, if as some students have surmised the phenomenon is one that undergoes periodic fluctuations.

Bearing on this question is a mathematical discussion by Professor C. F. Marvin, entitled, "Normal temperatures (daily): are irregularities in the annual march of temperature persistent?" Average annual temperature curves based on the averages of the means of each week over a period of years, may be well-covered mathematically in a curve of one or two harmonics. The residuals, which in a given period are much the same over a large part of the eastern United States, are mostly due to some extreme departures occurring in a single year of the record: which throws doubt on the existence of recurrent irregularities.

Professor Marvin's mathematical analysis of only 15-year averages shows that it is possible to get a surprisingly accurate, smoothed, normal annual temperature curve from a short record.

NOTES

The Monthly Weather Reviews contains so much material that these occasional notes in SCIENCE have by no means covered even a majority of the 150 contributions, not to mention hundreds of abstracts and other items of meteorological interest, published during the past year. For a brief summary and mention of many of the important contributions published during 1919, and the reader is re

ferred to the American Year Book; and for the articles and notes themselves, to the Monthly Weather Review files maintained at all Weather Bureau stations, and at a few hundred college, university and public libraries.

7 Ibid., pp. 544–555, 4 plates, fig.

• Government Printing Office, Washington, D. C., printed for the Weather Bureau.

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upward at A is greater than that at D. The liquid must therefore flow from A to D.

It is evident from this discussion that a siphon can not operate if AB is greater than the barometric height for the liquid in question.

II. If we consider the pressures acting at C we will find that the pressure toward D is the atmospheric pressure minus the pressure represented by a column of liquid AB, while the pressure toward A is the pressure of the atmosphere less the pressure represented by the column of liquid DB. The resultant pressure is therefore toward D, determining a flow in that direction.

It is evident from this discussion that a siphon can not operate if AB is greater than the barometric height for the liquid in question.

III. The end D being closed, and the siphon filled, the pressure at D will exceed atmospheric pressure by an amount represented by the column of liquid DA, since all points at the level of A are now at atmospheric pressure. Upon opening D this excess pressure causes the flow, and the atmospheric pressure at A keeps the tube filled.

It is evident from this discussion that a siphon can not operate if AB is greater than the barometric height for the liquid in question.

The refrain with which each treatment concludes is a noteworthy element of uniformity, to be considered below. Special features of criticism are as follows.

I. Pressure at a point within a body of fluid is not upward or downward, to left or to right, north, east, south or west. It is without direction.

The pressure at A, whether inside the tube or outside, and whether the siphon be flowing or not flowing, is never greater than the pressure at D.

The flow of a liquid between two points does not necessarily take place from high to low pressure. See the discussion below, based on Bernoulli's principle, of this particular

case.

II. As above stated, pressure in a body of

fluid is without direction. The pressure at C is neither toward A nor toward D, and certainly does not have unequal components in these two directions.

III. Except the concluding refrain, this treatment correctly represents the facts, and shows at least why the siphon ought to start flowing. Curiously enough, Bernoulli's principle and the law of diminution of potential energy having been known for a long time, little attempt is made to show what happens, and why, when the siphon is actually working, the discussions being chiefly hydrostatic.

If we assume that the siphon gives an example of steady frictionless irrotational flow of an incompressible fluid, an assumption probably justified as a first approximation, we can apply Bernoulli's principle. Then, for any given stream tube

p+ hdg+dv2= constant,

in which p represents fluid pressure, h height above any assigned zero level, g acceleration of gravity, d density of the fluid, and the speed with which it is moving.

Considering now the siphon when in steady flow, and assuming the reservoir indefinitely large, we find that the stream lines begin at the free surface, widely spread, the liquid flowing here at a speed approaching zero; converge into the orifice of the short limb, with much increased speed; traverse the entire length of the tube, supposed of uniform cross section, without change in speed, and that the stream emerges finally at this speed.

At the surface A outside the tube the pressure is atmospheric. Inside the tube it is less than atmospheric, for the stream has gained speed at the same level. As the stream ascends, at uniform speed, the pressure diminishes continuously, the least pressure being reached at the highest point. Descending, at constant speed, the pressure increases until at the lower orifice D the pressure is once more atmospheric, and the stream emerges in pressure equilibrium with the air surrounding it.

Taking a stream tube beginning at surface A outside the tube, and ending at D we have

P1=PP (atmospheric pressure),

v ̧=0, v2=▼ (constant speed through tube), and applying Bernoulli's principle

P+hdg=P+hdg+dV2,

whence

inside

V2=2g (h,h)=2gDA,

which expresses a simple interchange of potential and kinetic energy, corresponding dynamics. strictly with the facts upon the assumption that the operation is frictionless.

It will be easy to express the reduced pressure at the level A, inside the tube, by comparing two points at level A, one outside, the other inside

We have, outside

and thus

but

therefore

have

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Pi+h'dg+dV2=P+hdg,

P1 = P — }dV3,

At D

whence

We can now discuss the invariable refrain or coda found in all the type treatments. It appears to be based upon the assumption that a liquid can not exist with a negative pressure, or as sometimes expressed, under tension. This is hardly true; there is considerable experimental evidence to the contrary. Let us make this assumption, however, and limit the working height of the siphon to that which makes the pressure zero at the highest point.

Comparing points C (at level B) and D we

At C

}dv2 = dg (h1 — h2) ;

PP-dg (h, — h2).

Po=0, v。=V.

P2=P, v2=V.

hod g+dv2=P+hdg + }dv2;

(ho — h2) dg=P.

--

Now ho-h2 is the difference in level between D and B, which is thus shown to equal the barometric height for the given liquid, in

the assumed limiting case. The ordinary statement asserts that AB equals the barometric height in the limiting case, the loss of pressure at A inside the tube being overlooked, and the concept being hydrostatic rather than hydrokinetic.

This discussion is not original in substance; see some good treatises on hydro

HAROLD C. BARKER

THE AMERICAN ASSOCIATION FOR THE ADVANCEMENT OF SCIENCE SECTION E-GEOLOGY AND GEOGRAPHY THE Seventy-second meeting of Section E (Geology and Geography) of the American Association for the Advancement of Science was held in the Soldan High School building in St. Louis, Mo., on December 30 and 31. In the absence of Professor Charles Kenneth Leith, the vice-president elect of Section E, Dr. David White, chief geologist of the U. S. Geological Survey, was voted chairman for the St. Louis meeting, and presided.

The address of the retiring vice-president, Dr. David White, upon the subject, "Geology as Taught in the United States," was given on the morning of December 31 in the main auditorium, before a joint session of the Association of American Geographers, the American Meteorological Society, and Section E. This address will be printed in full in SCIENCE.

The vice-president of Section E for the coming year will be elected by the executive committee at its meeting in April. Dr. Nevin M. Fenneman, of the University of Cincinnati, was elected member of the council,

The program which was so full that each session overran the allotted time, comprised the following

papers:

The origin of glauconite: W. A. TARR. Glauconite is a hydrous silicate of iron and potash. The composition is variable, but the amount of potash rarely exceeds 8 per cent. The mineral is amorphous, and is usually some shade of green. It occurs as rounded grains and irregular areas in dolomites, limestones, conglomerates, marls, sandstones and shales. It is found in the Cambrian formations of Missouri, Oklahoma, Texas, South Dakota and Wyoming, and in the Cretaceous and Eocene formations along the Atlantic and Gulf coasts. Geographically and geologically, glauconite is associated with granites, usually being deposited

after a period of base leveling, when weathering had been proceeding a long time. This long-continued weathering is thought to have furnished colloidal silica, iron, potash and alumina to the sea water, where through the action of the saline matter in the sea water the silica and alumina were precipitated, while the iron was thrown down by oxidation. These colloids mingled in varying amounts and then absorbed the potash from the sea water, thus forming glauconite.

A Mauch Chunk Island in the Mississippian Seas of eastern Kentucky: WILLARD R. JILLSON, state geologist of Kentucky, Frankfort, Kentucky. In the eastern Kentucky coal fields on the divide between the Licking River and the Levisa Fork of the Big Sandy River, there exists an elongated structurally elevated area of between 700 and 1,000 square miles. This structural high has been called the Paint Creek uplift and is located so as to overlap parts of Magoffin, Morgan, Elliott, Lawrence, Johnson and Floyd counties. The Paint Creek uplift has a slight east of north major axis as mapped structurally on the Pottsville Fire-Clay coal. The normal dip at the surface is slightly to the south of east. The Paint Creek uplift culminates in two pinnacles, the Paint Creek Dome and the Laurel Creek Dome. There exists a maximum reversal of about 250 feet. The considerable amount of oil and gas prospecting drilling on these structures during the past two years has resulted in defining two pronounced oil and gas fields, one on either dome. Production is secured principally from the Weir sand which correlates with the Cuyahoga sandstone in the Waverley group toward the base of the Mississippian system. An examination of the well records of recent drillings in this locality shows an increasing interval between the Fire Clay coal of the Pottsville and the Big Lime (St. Genevieve-St. Louis) of the Mississippian, as one proceeds away from the highest structural points.

A summary conception of the structure of the Weir sand shows it to be much more steeply tilted than the persistent coals of the surface Pottsville. The absence of expected thicknesses of the Mauch Chunk on the top of this structure and the thickness of the Pottsville and Mauch Chunk on the sides coupled with the steeper inclinations of the Weir sands suggests an anticlinal island in the Mississippian seas at this point during the latter part of the Mauch Chunk period with unconsolidated Mauch Chunk sediments, subjected to subaerial erosion. Following early Pottsville times,

quiescent subsidence is conceived to have taken place, which was followed during the time of the Appalachian overthrusts by folding and faulting along, and transverse to, the major axis of the original Mississippian anticline.

A Geological Section from St. Louis to Kansas City: E. B. BRANSON.

The Pre-Moenkopi unconformity of the Colorado plateau: C. L. DAKE. The area over which the unconformity was studied embraces the region from the Zuni uplift in New Mexico west to the Little Colorado River in Arizona, and northwest to the vicinity of the Henry Mountains in Utah. Sudden changes in the thickness of the Moenkopi amounting to two hundred feet or more, in short distances, show local erosion of at least that magnitude during the pre-Moenkopi erosion interval. Data gathered by the writer tend strongly to confirm a hypothesis advanced by Cross that the Permian rests on progressively younger beds as the unconformity is traced westwards, the erosion amounting perhaps to all the Kaibab, the Coconino and the Supai formations. In other words the Moenkopi Red beds rest on the Kaibab formation in the area about the Grand Canyon and probably west of the Henry Mountains, while farther east they rest on the Goodridge (correlated by Girty with the Redwall) in the San Juan region, and probably on equivalent beds near Moab. This would involve the erosion of approximately two thousand feet of Pennsylvanian strata in the eastern portion of the area under discussion, the equiv alents of which are present farther west. This conclusion, if true, would place the pre-Moenkopi unconformity among those of larger significance in geologic history.

Notes on the geology of the Cove areas of east Tennesese: C. H. GORDON, University of Tennessee, Knoxville. Within the western foothills of the Unaka or Great Smoky Mountains in east Tennessee are a number of irregular open valleys known locally as "coves. "" The largest of these is Tuckeleeche Cove on Little River. Wear Cove to the northeast and Cades Cove on the southwest are about half as large. The coves are underlaid by the Knox dolomite uplifted in broad irregular domes with the overlying Wilhite slates outeropping in broad irregular bands around them. The more fertile soils of the coves early attracted settlers and each is now the locus of a prosperous settlement. This and the region to the southwest is the typical region of Safford's Ocoee rocks consisting of sandstones, conglomerates and slates

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