The competition of convict-labor.

In my criticisms of Mr. Butler's articles on this competition, I have shown that his method of stating the figures in totals, regardless whether these totals are in that relation which is the question at issue, namely in competition, is irrelevant.

Now, in his last rejoinder (Science, vii. No. 158), he brings some figures which are relevant in showing this relation in two trades in New York, hat and shoe making. In the former, for the year 1879, the ratio was 320 convicts to 5,267 free workers in the first trade, and 1,927 convicts to 26,261 in the second. The first ratio, he says, is about 4 per cent.' and the second something over 4 per cent.' In addition to questionable ethics and statistics already displayed, he now introduces very questionable arithmetic; for in reality the first ratio is 6 45 per cent, and the second 7.88. One who thus figures may well have, as he says, some hesitation in adducing fresh figures' ('fresh' in the sense of new, of course), ' for fear they may be summarily rejected as useless.' True, Mr. Butler, but not for the reason you give, "because they do not fit in some person's idea of how the course of nature' ought to go." "No' person' has said or implied any thing about ought' in relation to the ' course of nature' or any other relation.

Those who are organizing the working-classes into a political party, to obtain what they deem justice, are in earnest. Only one who has not felt the dread. ful sensation of being unable to sell his labor, when that is necessary to sustain life, can realize the bitterness and pain of such a situation. For every convict whose labor-product is sold in the market, a free laborer becomes superfluous, and therefore fewer work, or all are laid off temporarily, in that branch into which the convict is introduced. Here the 'political economist' of the prevailing order says, 'Find something else to do.' In most cases it is impossible.

There is another evil effect on free labor, resulting from prison-labor competition under any form; and that is, the effect it has to lower the rate of wages in any branch it enters. It must gain its market by underselling free-labor products; and however small the percentage, both as to its amount and of the decrease of its price, it lowers the standard of prices, including wages, in that entire branch.

To the workingman, a market for his labor is necessary to life to the state, a profit from the prison is not essential.

Shylock, surely not an insane humanitarian, truly says, "He takes my life who from me takes the means whereby I live." E. LANGERFELD.

Is the dodo an extinct bird? Have the recent excursions in theosophy, of my young friend Dr. Shufeldt (see Mind in nature, January and February), spoilt a very promising ornithologist to the extent of making him mistake a live Samoan tooth-billed pigeon (Didunculus strigirostris) for the astral body or the projection of the double of a perfunct dodo (Didus ineptus)? ELLIOTT COUES. Smithsonian inst., Feb. 14.

Corrections of thermometers for pressure.

The letter of Messrs. Venable and Gore in the last number of Science, on the effect of pressure on thermometers, contains a reference to the signal service, of such a character as to deserve a brief notice. It comes near leaving the impression that the service has just begun to consider a phenomenon which has been well known to most meteorologists, and to all engaged in accurate thermometric research, for more than fifty years. The letter, to which reply was sent from the office of the chief signal officer, made inquiry as to whether the service had ever published any thing on the subject, how thermometers used on Mt. Washington and Pike's Peak were compared with standards, and requesting information on the subject. The particular phase of the question which the service has had under consideration' was, whether the effect on the thermometers used in the service was sufficient to justify the application of a correction. To this end, some experiments had been made, the results of which were communicated to the writer of the letter. The correction necessary for Pike's Peak, which is the most elevated station from which the service receives reports, amounts to a few hundredths of a degree; and the propriety of its use is doubtful. The references quoted by the writers of the letter in Science were furnished them by the chief signal officer in his reply; the paper of Loewy and the memoir of Marck being quoted as among the latest and most complete. The phenomenon has by no means escaped the attention of writers. Among works likely to be easy of access, it will be found noticed in the 'American cyclopedia,' 'Johnson's cyclopedia,' Deschanel's 'Natural philosophy,' Balfour Stewart's Heat,' and doubtless many others of that class. It is noticed in numerous reports of the British association, especially in the reports of the committee on underground temperatures. One of the earliest investigations of the subject was by Egen (Pogg. ann. 1827). Sir William Thomson considered it, and provided against it, in 1850, in his verification of Prof. James Thomson's prediction of the lowering of the freezing point by pressure. Professor Rowland considered it, and allowed for it, in his research on the mechanical equivalent of heat. In Nature (1873-74) it was much discussed; and of course it has been a matter of vital importance in all modern deep-sea temperature-work, in the reports of which it receives full discussion. SIG.

Washington, D.C., Feb. 15.

Tadpoles in winter.

I have frequently observed tadpoles during winter, in ponds that were entirely frozen over, swimming about underneath the ice. Most of them were of large size I remember none being less than three or four centimetres in length.

Although, in this latitude, most of the frog-spawn is deposited during the first warm weather of spring, and the hatchings of these spawns develop into frogs before the following winter, yet spawns occasionally occur in late summer or early fall; and the hatchings of these late deposits fail to mature within the same season, and consequently, in favored localities, live until the following spring, when they transform into frogs. C. C. GREEN.

Mdidleport, O., Feb. 10.

Recent Proceedings of Societies.

Torry botanical club, New York.

Feb. 9. Dr. J. S. Newberry gave an account of the fossil flora of the New Jersey cretaceous clays, as far as known up to date, illustrated by the drawings thus far made. New material is constantly coming in, much of it new to science. Mr. Dudley exhibited specimens of unusually large hickory-nuts (Carya alba, Nutt), supposed to be abnormally developed. - Mr. Merrill showed a fungus of the genus Coprinus, collected in the Hibernia mine, New Jersey, five hundred feet from the surface.

Bourke, J. G. An Apache campaign in the Sierra Madre. New York, Scribner, 1886. 6+112 p., illustr 12°. $1.

De Morgan, A, the late. Newton: his friend: and his niece. Ed. by his wife and A. C. Ranyard. London, Elliot Stock, 1885. 6+161 p. 8°. 5s. 6d.

Greely, A. W. Three years of arctic service, an account of the Lady Franklin Bay expedition of 1881-84. New York, Scribner, 1885. 2 vols. 25+428, 14+444 P. 8°. (Subscription only.) Lancaster, A. Tableaux-résumés des observations météorologiques faites à Bruxelles pendant une période de cinquante années. Part i.: Temperature de l'air. Bruxelles, Hayez, 1886. 79 p. 16°. Prestwich, J. Geology, chemical, physical, and stratigraphical. In 2 vols. Vol. i.: Chemical and physical. Oxford, Clarendon pr., 1886. 24+477 P., 6 pl., illustr. 8°. (New York, Macmillan, $6.25)

Roig y Torres, R. Memoria acerca de la primera exposición internacional de electricidad celebrada en Europa. Barcelona, La casa provincial de caridad, 1885. 12-64 p. 8°.

Rred, A. Z. Evolution versus involution, a popular exposition of the doctrine of true evolution, a refutation of the theories of Herbert Spencer, and a vindication of theism. New York, Pott, 1885 12+273 p. 8°. $2.50.

Scribner's statistical atlas of the United States. New York, Scribner, 1883. 120 p, 151 maps, illustr. fo.

Servo-Bulgarian war, maps to illustrate the, with abstract of the treaty of Berlin, etc. Edinburgh, Johnston, 1885. 8°.

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MANUAL OF THE BOTANY OF THE ROCKY MOUNTAINS. Coulter (Wabash Coll), 8vo.. 496 pp. $1.85. Ivison, Blakeman, Taylor & Co., Pubs., New York.

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PHYSIOLOGICAL BOTANY: I. Outlines of the Histology of Phaenogamous Plants; II. Vegetable Physiology. Goodale (Harvard), 8vo., 560 pp. $2.30. Ivison, Blakeman, Taylor & Co., Pubs., New York.

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FRIDAY, FEBRUARY 19, 1886.

VIRCHOW ON ACCLIMATIZATION.

AT the congress of German naturalists and physicians held at Strasburg, Professor Virchow, the eminent pathologist, delivered an address on 'Acclimatization and the Europeans in the colonies,' of which the following is an abstract.

In these days of colonization, in which large numbers of human beings leave their homes and settle in foreign lands, under strange and unaccustomed conditions, the subject of the probable influence of such change upon themselves and their descendants becomes highly important from a practical point of view. The key to this problem is in the hands of physicians. With one or two notable exceptions, the subject has been neglected by scientific men. An opinion is current, and is often believed by those who send out colonies, that man is able to adapt himself to living on any part of the earth; that he is cosmopolitan in the widest sense. This view has allied itself to the monogenetic theory, which believes in the original common origin of all mankind from one pair, because thus this cosmopolitanism would simply be the return to former conditions. It was the changes from this primitive condition which caused the variations in the races of men.

Pathology is to be regarded, not simply as the study of the action of accidental causes upon man, which change his normal condition, but as necessary a science as physiology. Every biological science, zoölogy, botany, must have its pathology. It is a method of research, an experiment in vivisection which nature has made for us without shedding a drop of blood. From this point of view, all deviations, at first perhaps accidental, which become fixed by heredity, belong to the field of the pathologist. That such pathological variations are possible, one case is sufficient to show. A woman had a congenital defect of the arm, in which the radius was bent in a peculiar position, and the thumb of each hand was wanting. This woman's child was affected precisely in the same way, except that on one hand the thumb was in a rudimentary condition. In neither case was there an injury, but the accidental variation was transmitted. The question of the permanent acquisition of these pathological traits is a more difficult one.

The effects of a new climate upon the emigrant are well known, and are greater as the conditions of his new home differ more radically from those of his mother-country. A sort of new growth must take place, a new adaptation to the environment. A prominent symptom is a feeling of languor, which lasts for days, weeks, or even months. Two kinds of disease are apt to beset the emigrant the first is the climatic indisposition already mentioned; the second, the real climatic disease. The life of the individual is then in danger, until the question is decided whether his body has the power of adopting the new conditions or not. It is on this point that clinical observations in different countries are needed. In this organic transformation of the individual the fate of his descendants is involved. It is here that ethnologists become interested to find proofs for their theories that small variations become fixed and lead to racial differences. Experimental evidence on this point is still wanting.

The question of greatest interest to us is, To what extent has the white race, in its historic evolution, shown the power of adaptation? The white race is not a simple one, and distinctions must be made. The Semitic, as opposed to the Aryan branch, has a very great superiority in this respect. Again, the southern nations Spaniards, Portuguese, Sicilians have a greater power of adaptation than the northerners. In the colonization of the Antilles, the attempts of the English and French have been more or less disastrous, while those of the Spaniards have been quite successful. The general proposition, which is only a provisional one, seems to be that a southern people can emigrate to an equatorial region without danger. The readiness with which a population mixes with another is also of importance. The more southern Aryan peoples more easily assimilate with the Semitic element than the northern ones. This Semitic element, which appears early in the Phoenician expeditions to foreign lands, is best suited for founding permanent colonies. To this day, relics of the settlements all along the coast of the Mediterranean, made by Semitic people, can be traced.

Those white races which cannot become acclimatized without great loss may be called vulnerable, and the regions of the globe which are open to them are very limited.

North America is one of these favorable regions. The French were able to found a flourishing and

active colony in so cold a country as Canada. The United States, with its mixture of nationalities, is another such region. The acclimatization, however, is not brought about without considerable change in the mental life and characteristics of the people. The Yankee is strikingly different from the Englishman. The real sign of the longevity of a colony is the relative birth-rate and mortality as compared with that in the mothercountry. The general result is, that, the farther south we go into the tropical countries, the lower does the reproductive power of the colony become, until in a few generations sterility is more and more prevalent. Of this the Creoles are a good example. The special cause of this degeneration has been regarded by physicians as a lack of the formation of blood, a general anaemia. This explanation, however, is not final; and a further cause, such as the presence of micro-organisms in the water, is to be looked for. The great prevalence of liver-disease in such cases offers a valuable clew.

It is considerations such as these which make us feel the want of thorough scientific research of the conditions which control the foundation of colonies. When these are known, it will no longer be necessary to make sacrifices of thousands of men in an idle attempt to make inhabitable some desolate unfavorable region. The order of national adaptability to new environment we have made out to be, first, the Jews; then the Spaniards, Portuguese, etc.; then the southern French and the northern French; and lastly the Germans. The remarkable immunity of the Jews is a question of great interest. What share in this peculiarity is due to their peculiar hygiene, choice of food, devotion to the home sentiment or to their occupation, is an open question.

THE TRADE IN SPURIOUS MEXICAN ANTIQUITIES.

THE present is a museum-making era, and future generations are perhaps to be congratulated that such is the case; but this wide-spread fancy for hunting and hoarding relics has given rise to minor features greatly to be deplored. The increased demand has given a considerable money value to antiquities; and this has led to many attempts, on the part of dishonest persons, to supply the market by fraudulent means. To such a degree of perfection has the imitation of some varieties of relics been carried, that detection is next to impossible. Doubtless in time most of the spurious pieces will be detected and thrown out; but in the mean time they will have made an impression upon literature, and upon the receptive mind of

the public, that is most difficult to eradicate. In view of these facts, it would seem to be the duty of interested persons to publish, at the earliest opportunity, all reliable information tending to expose frauds and correct erroneous impressions.

It is perhaps in stone, and especially in steatite, that frauds are most frequently attempted; but the potter's art has not escaped, and most of our collections contain specimens illustrating the skill of the modern artisan and the carelessness of collectors. Although we need not go beyond our own borders for illustrations of this statement, I wish here to call attention to some examples from Mexico. In pre-Columbian times the native potter of that country had reached a high degree of skill in the handling of clay; and Spanish influence has not been sufficiently strong to greatly change the methods, or restrict the manufacture. very easy, therefore, for the native artisan to imitate any of the older forms of ware; and there is no doubt that in many cases he has done so for the purpose of deceiving. A renewed impetus has been given to this fraudulent practice by the influx of tourists consequent upon the completion of numerous railways.

It is

The variety most frequently imitated is a soft, dark ware, sometimes ferruginous, but generally almost black. The forms are varied, including vases, statuettes, pipes, whistles, and spindlewhorls, all of which are profusely ornamented. One notable form is a vase modelled in dark clay, and bristling with a superabundance of figures in relief, which give a castellated effect. A large piece recently acquired by the national museum was designated a miniature stone fort' by the collector, and a second piece could as readily be called a Chinese pagoda in clay.

The body of these vases is usually a short, upright cylinder, mounted upon three feet, and is profusely decorated with incised patterns and with a variety of ornaments, including human and animal figures in the round. A row of figures surrounds the rim, giving a battlemented effect; and a high conical lid, surmounted by a human figure, is usually added. The body of the vessel is modelled by hand; and the flatter portions of the surface are rudely polished, and covered with incised patterns. The attached figures are formed separately in moulds, and afterwards set into their places. Certain parts are further elaborated by means of figured stamps. After finishing, the vases are prepared for market by burial for a short time in the moist earth, or, more frequently perhaps, by simply washing them with a thin solution of clay. The deposit of clay is afterwards partially wiped off, leaving the lines and depressions filled with the light