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The cause, here as in Russia, is the glorification of "labor"-apparently synonymous with cessation of labor, at any rate for a price pro portioned to its value.

When a professor does not actually "quit his job," the public supposes he is giving the same service as formerly. In fact he may be simply meeting his classes as before, some ten or twenty hours in the week; the rest of his active time, which should be spent in preparation, study and research, is under present conditions too often dissipated in chores of house and garden, for which "help" is no more to be had. In effect the professor has "quit his job," for half time and in that half is situated somewhat like Professor Pavlov.

The irony of it is that the professor is the last man in the world to shirk his professional work, which is also his pleasure; but the topsyturvy economics of the day are forcing many to do so.

A MEMBER OF THE EXPLOITED CLASSES

QUOTATIONS NITROGEN FROM THE AIR AND THE BRITISH GOVERNMENT

THE report of the Nitrogen Products Committee has at last been allowed to emerge from the seclusion of the government pigeon-hole, in which it has reposed, in type, for at least seven months. It is a voluminous document of over 350 pages, containing the results of nearly three years' work, largely voluntary, on the part of a number of scientific men, who in that period explored in great detail the statistical and economic aspects of the nitrogen problems and also supervised much experimental research. The latter was devoted especially to the Haber process for the synthetic manufacture of ammonia by the direct union of its elements, nitrogen and hydrogen-a process which, coupled with the oxidation of the ammonia to nitric acid, undoubtedly enabled Germany, cut off from supplies of nitrate from Chile, to continue the war longer than would otherwise have been possible. The general principles of that process were familiar enough in this country, but acquaintance

with the technique of its operation was confined to Germany. However, the committee made such progress towards remedying this deficiency that in their report they feel justified in recommending the immediate establishment of the process on a "commercial unit" scale in this country and its extension up to a minimum of 10,000 tons of ammonia annually.

For this purpose they suggest the utilization of a factory at Billingham-on-Tees. The Explosives Department of the Ministry of Munitions decided to start this factory in a hurry, and perhaps in advance of the technical knowledge available at the time, towards the end of 1917; but their attitude towards it was somewhat Laodicean, and it has not been finished. Its completion would cost a considerable sum, but the committee's view is that, as a matter of national insurance, we ought to be in a position to manufacture nitrates artificially in this country, since, from the military aspect, we cannot afford the risk of being dependent on saltpeter imported from Chile for the nitrogen compounds which are indispensable for modern high explosives. Perhaps the best solution would be for private enterprise to take over and equip the factory, with some measure of government control and interest; and the appearance a few weeks ago of an advertisement inviting offers for it suggests that this is the direction in which events are moving. It is believed, indeed, that an important group of firms is in negotiation for the place. In this connection it must be remembered that nitrates are as essential in peace, for fertilizing purposes and the manufacture of mining explosives, as they are in

war.

A cheap and abundant supply of electric power being essential for the commercial success of some of the processes of fixing atmospheric nitrogen, the committee considered very fully the question whether this condition can be met in the United Kingdom. In particular, they investigated the possible advantages of employing preliminary processes of carbonization and gasification in connection with large electric power stations, instead of firing

the coal direct into the furnaces of steam boilers. Such methods offer the attraction that they permit the recovery of by-products that are lost with direct firing, and it is, therefore, disappointing to find that the committee's conclusions are adverse. They conclude that, in the present state of knowledge, the direct burning of coal under steam boilers forms the cheapest method of generating electricity on a large scale from coal, even when the indirect processes are credited with the revenue obtainable from the sale of the recovered by-products. What is still more unfortunate from the point of view of those who hope for an increased supply of homeproduced liquid fuel, as well as cheaper electricity from capital power stations with gasfired boilers-they make out that the advantage of direct firing increases with rising costs of coal and labor.-The London Times.

NOTES ON METEOROLOGY AND
CLIMATOLOGY

RAINFALL (AND snowfall) oF THE UNITED
STATES1

THE Weather Bureau has just issued a reprint from the Monthly Weather Review entitled "Seasonal distribution of precipitation and its frequency and intensity in the United States," by Joseph B. Kincer. Three reviews and abstracts are included in, the reprint: "Some characteristics of the rainfall of the United States," by R. DeC. Ward; “New seasonal precipitation factor of interest to geographers and agriculturalists," by R. M. Harper; and "The snowfall of the United

1 Cf. notes on this subject in SCIENCE, July 19, 1918, N. S., Vol. XLVIII., pp. 69-72 (snow, SCIENCE, February 11, 1916, N. S., Vol. XLIII., pp. 212-214).

2 September and October, 1919, Vol. 47, pp. 624– 633, 695-696, 7 graphs, 30 maps-13 in text and 17 full-page lithographs. (For copies, apply to "Chief, U. S. Weather Bureau, Washington, D. C.'')

3 Scientific Monthly, September, 1919, Vol. 9, pp. 210-223.

4 SCIENCE, August 30, 1918, N. S., Vol. XLVIII., pp. 208-211.

States," by R. DeC. Ward. Since these three papers are easily available, this note will cover only Mr. Kincer's article and the graphs added to the reviews of Professor Ward's two papers.

Here are published, for the first time, reliable and detailed maps of the average rainfall of the whole United States for each month. The topographic (hachured) base-map used shows at once the close dependence of rainfall on topography as it affects precipitation of moisture from the prevailing westerly winds. We have long known of the marked spring and early summer rainfall maximum in the prairies and Great Plains; but these monthly maps give us almost a moving picture of the wave of rainfall which spreads northward and westward as the warm southerly winds blow in day after day from the Gulf of Mexico. From its February position across east Texas, northwest Arkansas and southern Illinois, the 3-inch monthly rainfall line in March has moved westward into Oklahoma, central Missouri and northern Illinois; in April, to central Texas, central Oklahoma, eastern Kansas and central Iowa; in May, to the 101st meridian in south Texas, across the Panhandle into northeastern New Mexico, through western Kansas, west central Nebraska, the Dakotas and northern Minnesota, and in June still farther westward in the central and northern Great Plains-in Montana even to the Rockies. By June in the southern Plains and by July in the northren Plains the spring-time flood of moist air has spent itself, and the rainfall lines are beginning to retreat-eastward as the summer passes, and southward as the coldness of the oncoming winter renders much precipitation impossible. The four maps of precipitation by seasons summarize this same movement of the isohyets. With such a series of maps before one it is obvious that the Gulf of Mexico and the open country to the north and northwest allow our prairies and plains to be so productive.

If the conditions year after year were like those shown on these maps of average rainfall, we should not have been experiencing or

5 Scientific Monthly, November, 1919, Vol. 9, pp. 397-415, map.

reading of the great droughts, recently ended, which were at their worst in west Texas and the northern Great Plains. The flood of warm, moist air from the Gulf is variable in size and duration. These variations are felt most near its western and northwestern limits, where farmers have learned to look on partial crop failures as normal. This variability, which is the most important aspect of rainfall, aside from the average amount, is clearly brought out by Mr. Kincer in a number of graphs and maps. In drought years as well as in years of plenty, farmers are inclined to believe in stories of progressively decreasing or increasing rainfall: comparisons of rainfall averages by successive 20-year periods show, however, that in this region there is no perceptible progressive change in rainfall.

In years of decreasing rainfall, real-estate agents for the semi-arid lands of western Kansas explain to prospective buyers that although the total rainfall is decreasing, the decrease is mostly confined to the washing and flooding downpours, and that the proportion of rains of beneficial amount is increasing. They are discussing another essential element which must be considered in comprehensive rainfall discussions. Mr. Kincer presents maps showing the average annual number of days with precipitation 0.01 to 0.25 inch, 0.26 to 1.00 inch, and 2.00 inches or more. Further details of rainfall intensity are given on maps showing the average annual number of days with precipitation more than 1.00 inch in an hour, and the maximum precipitation in 24 hours. Two more maps which might be called drouth maps" show the percentage of years with 30 consecutive days or more without 0.25 inch of rainfall in twenty-four hours from March 1 to September 30, and the greatest number of consecutive days without 0.25 inch of rainfall from March 1 to September 30. These are all based on the rainfall data for the 20-year period, 1895-1914.

There are three snow maps presented. A large one shows the average annual snowfall of the United States, 1895-1914, drawn on a topographic base-map with close attention to the effects of altitude and exposure. The other

two maps show the average annual number of days (1) with measurable snowfall, and (2) with snow cover. In the eastern United States (except near the Atlantic) the line of one day with snow cover (the average of several days in one winter, with no days in several years) is near the 33d parallel of latitude; that of 30 days with snow cover lies close to the 39th parallel; that of 60 days near the 42d; that of 90 days near the 43d, and that of 120 from near the 44th in the East to the 47th in Minnesota. As a broad generalization, the number of days with snowfall is about half the number of days with snow cover.

The publication of these interesting precipitation maps with the discussion makes us hope that still another year will not pass before the issue of the long-expected precipitation section of the Atlas of American Agriculture, with its colored maps, carefully made graphs and detailed discussion. Still later, the folio on temperature and the other climatic elements are to come.

WASHINGTON, D. C.

CHARLES F. BROOKS

SPECIAL ARTICLES

INTERSEXES IN DROSOPHILA SIMULANS

ON the first day of January, 1920, a stock of Drosophila simulans Sturtevant from Rochester, Minn., was found to contain inter

sexual individuals. Over 200 such intersexual specimens from this stock and derivatives of it have now been examined. About a dozen of them have been dissected and about the same number have been cleared in KOH and examined in balsam. All these specimens apparently belong to a single type. Male and female parts are both present, as will appear from the following table.

The intersexes are sterile, inasmuch as their gonads are almost, if not quite, absent. Their sexual behavior seems to agree best with that of the normal females. They are courted by males, but mating has not been seen.

1 For a description of this species see Psyche (1919), 26, p. 153.

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Crosses of normals from the intersex stock have made it possible to study the character. The intersexes are modified females-i. e., they have two X-chromosomes. This is shown by the fact that in cultures in which half of the males show sex-linked recessive characters but all the females are wild-type, the intersexes never show these sex-linked characters. This relation has been found to hold true for three sex-linked characters that are not closely linked to each other; and the intersex gene itself has been found not to be sex-linked (see below). Therefore the relation just noted can not be due to linkage between the intersex gene and the sex-linked genes in question.

Numerous crosses of the intersex stock to unrelated stocks have never given intersexes in F1, but have frequently produced them in F2. The intersex character is therefore recessive.

Pair matings that have produced intersexes have given a total of 5109: 165 intersex: 754♂. There is an excess of males, but this is evidently a 3:1 ratio of females to intersexes, indicating not only that the gene is recessive but also that it is not sex-linked. The final proof of the latter point has been obtained through the discovery that the intersex gene is linked to the autosomal recessive gene for "plum" eye-color. Three F, pairs from a mating between the intersex stock and the plum stock have given in F:

1

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The absence of the intersex plum class shows that the two genes are linked; and plum is known to be an autosomal recessive.

It has been shown by Morgan and Bridges' that individuals of D. melanogasters that are partly male and partly female are produced, though only rarely, by most stocks. These "gynandromorphs" have been shown, by genetic evidence, to have two X-chromosomes in their female parts and only one X in their male parts. They are sex mosaics, and each part develops as it would in a whole animal of the same genetic constitution. There is strong evidence that the intersexes described here are not of this nature. The male and female parts in them probably both possess two X-chromosomes. This has been shown as follows. A total of 104 intersexes have been produced by females heterozygous for the sexlinked gene for "yellow" hairs and bristles. Half of these intersexes-about 50-must then themselves have been heterozygous for yellow. If the intersexes are really gynandromorphs, the male parts at the posterior end of the abdomen should have contained a single Xchromosome, and in about half of the specimens that were heterozygous for yellow (i. e., in about 25 individuals) this should have been the yellow-bearing X. As Morgan and Bridges have shown, these parts should then have borne yellow hairs and bristles. The 104 intersexes were all carefully examined for this point, and none of them had yellow male parts.

We may conclude that the intersexes are females, modified by a recessive autosomal mutant gene that causes them to show male parts, though these parts themselves still have two X-chromosomes. The normal sex-determining mechanism is not affected at all, but the end result is modified by a gene that is not even in the sex chromosomes. It has

2 Carnegie Inst. Washington (1919), publ. 278, pp. 3-122.

3 I have unpublished data on exactly similar cases in D. simulans itself.

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THE thirteenth annual meeting of the Illinois State Academy of Science was held at Danville, Illinois, February 20 and 21, 1920, under the presidency of Dr. Henry B. Ward, of the University of Illinois.

The principal items of business transacted were the following: The academy voted unanimously to become affiliated with the American Association for the Advancement of Science under the terms adopted by the council of the association at the St. Louis meeting. It was voted that one half-day session of the next annual meeting be devoted to section meetings and the following sections were provided for: medicine and public health; biology and agriculture; geology and geography; chemistry and physics; mathematics and allied sciences; the science of education and education in science. It was voted that the council of the academy be empowered to select chairmen for these sections. The committee appointed last year to secure affiliation of science clubs in high schools with the academy reported five such clubs which had accepted the terms of affiliation, two of these taking national membership under the plan of affiliation with the American Association for the Advancement of Science.

In addition to the regular program of scientific papers, Dr. Henry B. Ward, president of the academy delivered an illustrated lecture on Alaska.

The following officers were elected for the ensuing year: Dr. Henry C. Cowles, University of Chicago, president; Dr. Chas T. Knipp, University of Illinois, vice-president; J. L. Pricer, State Normal University, Normal, secretary; Dr. W. G. Wat▲ Proc. Nat. Acad. Sci. (1916), 2, pp. 53-58; Jour. Exper. Zool. (1917), 22, pp. 593-611, and elsewhere.

5 Biol. Zentralbl. (1912), 32, pp. 65-111, and elsewhere.

• Proc. Nat. Acad. Sci. (1916), 2, pp. 578-583, and (1918) 4, pp. 373-379.

erman, Northwestern University, treasurer. Dr. A. R. Crook, State Museum, Springfield, is ex-officio librarian of the academy, in charge of the sale of back numbers of the transactions and of the exchange of current issues.

One hundred and five new members were elected to the academy.

The following are the titles of the papers presented at the different sessions:

Development of smokeless fuel from Illinois coal: PROFESSOR S. W. PARR, University of Illinois, Urbana.

Tastes and odors in the Danville water supply in the summer of 1919: DR. EDWARD BARTOW and R. E. GREENFIELD, Illinois State Water Survey, Urbana, and H. N. ELY, Superintendent, Interstate Water Co., Danville.

A new test indicator for water analysis: R. E. GREENFIELD, Illinois State Water Survey, Urbana.

The founding of sanitary districts: DR. EDWARD BARTOW, Illinois State Water Survey, Urbana. Some comments on the present status of tuberculosis: DR. WALTER G. BAIN, St. John's Hospital, Springfield. During the war, chief of the laboratory service of the U. S. Army General Hospital No. 8.

Statistical study of the incidence and mortality of influenza in Illinois: DR. HENRY B. HEMENWAY, Division of Vital Statistics, State Department of Public Health, Springfield.

Report of progress at Illinois State Museum: DR. A. R. CROOK, chief of Division of State Museum, Springfield.

Gaining and losing power: C. L. REDFIELD, Chicago.

The progress of barberry eradication in Illinois: L. R. TEHON, assistant pathologist, U. S. Department of Agriculture.

Road oil and its uses: DR. A. F. GILMAN, Illinois Wesleyan University, Bloomington.

The absorbtion of oxides of nitrogen formed in silent discharge: DR. F. O. ANDEREGG, Purdue University, Lafayette, Ind.

A possible standard of sound; a further study of wave form and operating conditions: DR. CHAS. T. KNIPP and C. J. LAPP, University of Illinois. Evidence that catalase is the enzyme in animals and plants, principally responsible for oxidation:

DR. W. E. BURGE, University of Illinois, Urbana. New species of fossils from the Devonian limestone in Rock Island County, Illinois: Dr. T. E. SAVAGE, University of Illinois, Urbana.

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