the ordinary type, though having some of the imperfections that Dr. Albrecht notes. I can easily understand the cheapening in cost he suggests.

Recently I have received a book on this breed, containing considerable tabular matter, but mostly straight reading, made by this process, double spaced between the lines, type of the normal size of the typewriter, printed on one side of the sheet only, which is really easier on the eyes than the ordinary print, excelling even the admirable type used in SCIENCE in that respect.

I thoroughly agree with Dr. Albrecht in thinking that this method, particularly if improved as he suggests, might help to solve the financial problems that often present themselves to the impecunious research man who wants to let other people know what he has been doing.

And while we are about it, why not follow the suggestion of Dr. Metcalf on the same page, and adopt a character to convey the sound of "th"? I would suggest that the adoption of the crossed "h" which he mentions might lead to the same sort of confusion that some of us have experienced in reading the books of the eighteenth century in which the long "s" was used, and the difficulty in separating it from an "f.” Why not take one of the letters from other languages, as the Greek ?

SPRING HILL, TENNESSEE

LUCIUS P. BROWN

In reference to the suggestions of Mr. Albrecht in regard to photographic reproductions of typewriting, I, some years ago, prepared a special text in physics for freshmen. I was unable to have it published in the usual way because the price of the book to the student would have to be so great that it seemed unreasonable. I then wrote the whole text on the typewriter, attached cuts in their place on the page and arranged with a firm in Cincinnati to photograph each page and make zinc etchings. This they did for $293.00. These were then sent to the Reformatory at Mansfield, Ohio, where the books were printed and bound for $150.00-500 copies. This made a total of $443.00 and the books could then be sold to the students at $1.25, which not only met all expenses but cleared a small margin for the department.

MIAMI UNIVERSITY

J. A. CULLER

EXPLORATION OF THE ETOWAH MOUNDS

THE department of archeology, Phillips Academy, Andover, Mass., has carried on two seasons' exploration at a large village site and mound group in northern Georgia. About one hundred stone graves

were discovered which contained some engraved shells, various ornaments, pottery vessels and some engraved copper plates. The eminent authority on Mexican cultures, Mrs. Zelia Nuttall, examined the collection at Andover and suggested several lines of comparison between certain of the human figures and those observed among Toltec and Mayan remains. It is not claimed that any connection exists, but some of the comparisons are exceedingly striking.

Two complete sarcophagi were shipped to the Andover museum, set up, filled with Georgia earth and the skeletons and objects placed in natural position. Five such graves were shipped to other museums and have attracted considerable attention. Any museum director or curator who wishes one of these graves and its contents can correspond with me at Cartersville, Georgia.

WARREN K. MOOREHEAD

METAPSYCHICS

IN my "Zoology" (1922), page 536, I have given an explanation of the term Metapsychics, which may perhaps later come into more general use. It may be worth while to record the history of this term, before it is forgotten. I published it in The Dial (Chicago) of February 1, 1905, page 86, with a definition. In the Daily Graphic (London) of February 9, 1905, page 7, I read that quite independently Professor Richet had proposed the same term at a meeting of the Psychical Society. If there is an earlier publication of the word, I have not found it.

T. D. A. COCKERELL

QUOTATIONS

THYROXINE

RECENTLY the Chemical Society resolved to award the Edward Frank Harrison Prize for 1926 to Dr. C. R. Harington, of University College Hospital. The achievement which has earned this tribute from the colleagues of Dr. Harington has been the synthesis in the laboratory of the active principle of the thyroid gland-the substance thyroxine.

It was only in June of the present year that those who follow the literature of chemistry learnt of the progress of his labors, and discovered Dr. Harington on the very threshold of a complete success. Two papers under his name appeared at that time in the Biochemical Journal. The first described a greatly improved method for the separation from thyroid tissue of the hormone in a chemically pure state-a method, moreover, which was not found wanting when pursued in an industrial laboratory. The second paper proceeded to the chemical analysis of the pure

In one particular only was this formula uncertain. The position of the four iodine atoms could not be definitely affirmed. It had been possible to remove these from the molecule of the natural product. It had been possible by two independent methods to synthesize in the laboratory the iodine-free substance by a series of reactions accurately defining its structure. It had not then been found possible to introduce into the synthetic substance those four atoms of iodine which, in their proper orientation, would create the molecule which is thyroxine.

In a joint communication by Dr. Harington and Professor G. Barger to the December meeting of the Biochemical Society, the final solution of the problem was unfolded. Commencing with hydroquinone and tri-iodo-nitro-benzene materials which inspired a press report to describe, a little optimistically, the synthesis of thyroxine from "coal tar products and iodine"-a series of classical organic reactions were adapted with masterly tidiness to the issue of a product of the above chemical structure. The substance was chemically indistinguishable from that isolated from thyroid glands. The chemical chapter is complete, the biological story opens. Use was made of the now well established quantitative effect of the hormone on the basal metabolic rate.

Two myxoe

dematous patients were chosen. Their basal rates were respectively 32 and 45 per cent. below normal. Intravenous injection of the synthetic substance was spread over six days to a total dose of 14 mg, and the basal metabolic rates rose, in the first case to 6 per cent. short of normal, and in the second to 3 per cent. above normal. There occurred a coincident fall in body weight and increase in the pulse rate. Such activity was quantitatively as great as that given by natural thyroxine. Physiologically the two substances were indistinguishable. The structure of thyroxine requires the existence of two stereoisomeric forms, and we may suspect that the thyroid gland, by virtue of that elusive asymmetry of vital activities, synthesizes and employs but one of these isomers. That the substance obtained from the gland is the racemic mixture is due to the inevitable racemization which accompanies the process of separation, and it is not improbable that a resolution of thyroxine into its active forms will show that physiological activity is restricted to one only of these. This form should then be twice

The methods of With thyroxine

as active as the materials yet tested. physiology must now take the field. to hand there is available a means for the quantitative study of the rôle of the hormone and the function of the gland.

The committee which resolved to award the Harrison prize to Dr. Harington comprised the presidents of the Chemical Society, the Institute of Chemistry, the Society of Chemical Industry and the Pharmaceutical Society. Thus have the theoretical and applied interests of a science united to acknowledge the common benefit in a great academic adventure.-The British Medical Journal.

SCIENTIFIC BOOKS

Studies of the Variation, Distribution and Evolution of the Genus Partula; the Species inhabiting Tahiti. By HENRY EDWARD CRAMPTON, Ph.D., professor of zoology, Barnard College, Columbia University; curator of invertebrate zoology, American Museum of Natural History. The Carnegie Institution of Washington, 1916. 307 pages quarto. 33 plates.

ONE of the most important contributions to our knowledge of animal evolution, perhaps the most important yet published in the twentieth century, is Dr. Crampton's "Study of Partula," a genus of land snails found in the forests of islands of the South Seas. The central problem of evolution is, as indicated by Darwin, that of the origin of species. There exist on our earth a prodigious number of kinds of animals and plants. These are variously interrelated, and their relations are shown in their structure and development and are connected with their distribution and that of their ancestors in space and time. The features of their relations and the causes of their diverging progression constitute the factors in evolution. The determination of these factors in detail is to science vastly more important than the fate of any or all philosophies of evolution. And the study of these facts is essentially, as Darwin, Wallace, Wagner, Ortmann, Kerr and others have shown, an out-ofdoor subject, on which not much light can be thrown by closet studies. Studies in greenhouses or breedingpens have been devoted mainly to problems of heredity, a matter of the greatest importance to biology, but not necessarily illuminating the problem of origin of species.

Even the meaning of species has been confused through indoor studies. A fairly inclusive definition is that a species is a definable kind of animal or plant which has run the gauntlet of life and which has endured. The imitation species of the laboratory have arisen through much the same elements, yet they have

not been tested for endurance in the gauntlet of life. For the most part they could not endure in the open because their selection is not based on fitness for survival, and because, without segregation, they would soon be lost by interbreeding with the prepotent mass. As is the case with actual species, the "creations" of the breeder begin with individual variation, this continued through heredity, restricted by selection and kept apart by segregation. In nature, species originate in essentially the same way, except the period of testing for endurance is enormously prolonged. Selection is "natural" and the segregation is a feature of geographical distribution. Where the breeder of flies segregates in bottles, nature uses mountains, deserts, seas, climates and food conditions, in developing her species. But every one of these rests on all of at least four factors or conditions, two internal, variation and heredity; two external, selection and segregation. In every species results of each of these traits are shown. Hence they are factors in evolution. By many recent writers, these external factors, especially the last, are overlooked or slurred, as though divergent change could take place in vacuo by the operation of a "law of evolution." The dictum of Wagner, "Ohne Isolirung keine Arten," holds good, for the final segregation of all forms is associated with "räumliche Sonderung" or separation in space from the main stock. Precisely the same thing occurs with our temporary species or "creations," but these are too recent to be tested through "running the gauntlet of life" or the prevention of mass breeding.

The land snails called Partula consist of many species living on trees, the individuals relatively stationary and closely limited by local conditions. Dr. Crampton has undertaken the detailed study of these snails in all the minute features which concern their life and distribution. The "headquarters of the group" are in the Society Islands (Tahiti, Raiatea), though species are widely scattered elsewhere on various other island groups. None are found in the Hawaiian Islands, where their place is taken by a parallel group, the Achatinellida, already famous through the work of the late Dr. John T. Gulick.

Dr. Crampton has made four journeys to Tahiti and the other islands of the South Seas. In these trips more than 80,000 specimens, taken from two hundred different valleys, were obtained and studied, covering many different species and subspecies. The work had three purposes: first, the study of results of "isolation and environmental influences as conditions or factors of biological differentiation. These have been variously estimated in the writings of naturalists from Darwin, Wagner, Murray, Wallace, Gulick and Romanes to Allen, Jordan, Ortmann and

others . . . who have accorded to the 'environment' almost all degrees of efficiency, from omnipotence to impotence."

The second purpose was to continue Dr. Albert G. Mayer's work on inheritance of shell and color characteristics; the third to bring back living material for studies in selective breeding of pure and hybrid strains. But the species must themselves be known before much advance in this line is possible. It was found that each island, even in the same group, had its own species of Partula which (except in rare cases) occur nowhere else. The study of these cases throws much light on dispersal and migration as well as on certain matters of geology. It was found that some species range widely over a whole island and others are restricted to a few valleys, or even to one. These conditions give rise to numerous subspecies or varieties. In connection with the singularly accurate observations of Partula by Andrew Garrett in the sixties, it has been possible to trace the relative age of several species. Mutations, or wide individual variations, occur frequently, "so that it can not be regarded as a unique feature." The effect of environment in originating new species is negligible. Dr. Crampton regards isolation as a "condition" rather than a "factor" in species forming. This seems a matter of words. Barriers act as obstructions behind which new species form, thus becoming a negative factor. Dr. Crampton finds in the distribution of Partula evidence of large subsidence in the Pacific Area, causing disconnection among islands and mountain peaks, with parallel effects on the snails they bear.

All the species and subspecies mentioned in this monograph are beautifully figured in color. There are also numerous maps and photographs illustrating the wild and picturesque scenery of the Society Islands.

STANFORD UNIVERSITY

DAVID STARR JORDAN

SCIENTIFIC APPARATUS AND

LABORATORY METHODS

A SIMPLE LABORATORY QUARTZ MERCURY

LAMP

A SIMPLE and efficient quartz mercury lamp, with electrodes not sealed in, and easily constructed in the laboratory for from two and a half to five dollars, is shown in Fig. 1.

A is a quartz tube of 0.6-1.0 cm bore and 5-8 cm long. B and B' are quartz capillary tubes of 1 to 2 mm bore and approximately 10 cm long, bent at C and C' nearly perpendicular to A. The bend CD is approximately 2 cm long. Both capillary legs are

constricted at two or three points, which serve to damp the oscillation of the arc.

The lamp stands in small beakers or cups M and M', filled with mercury and provided with iron wire electrodes H and H'.

In order to fill the lamp with mercury, the ends of the legs are dipped in the mercury pools, while the portion A is tilted and lowered as far as possible. The portion A is then heated to expel a part of the air from the apparatus. As the tube cools, mercury flows down into A, which is now boiled to drive all the air and moisture out and to completely fill the lamp with mercury. The lamp, again brought to the upright position as shown in the figure, is ready to be operated.

To start the arc, a point of A is heated until the mercury in the tube boils and the arc starts. It becomes perfectly steady within five minutes.

A lamp was constructed with the following dimensions:

A 0.6 cm. inner diameter

1.3 cm. outer diameter 7.0 cm. long

B 0.2 cm. inner diameter 0.6 cm. outer diameter 10.0 cm. long

CD 2.0 cm. long

It was operated with 130 volts at the generator, through a 100-watt tungsten and a 20-watt carbon lamp in parallel and gave an extremely steady arc 4.5 cm long, the arc voltage being 78 volts and the current 0.7 amp. It has been in use nearly every day for over three months without causing any trouble. It has been operated for seventy-five hours continuously without a single readjustment. While

Fig.2

the generator voltage varies between 120 and 150 volts, the potential drop across the arc varies from 67-110 volts, corresponding to 19-21.6 volt/em gradient when the current is .65-8 amp.

Another lamp of the same dimensions, except that A is of 0.7 cm outer diameter and 8.5 cm long, was constructed. Operated with 125 volts at the generator, this lamp gives an arc of 4 cm length, the are voltage being 75 volts and the current 0.7 amp. With higher voltage, the tube A must be cooled by a strong air current. When fed with 150 volts, this lamp gives a very steady are 7 cm long, the arc voltage being 100 volts and the current 1.2 amp. Air is blown through small holes along a tube against the entire length of the arc.

After the arc is run for from ten to fifteen hours, the mercury transferred to the negative pole may be brought back to the positive pole with a pipette.

This type of quartz lamp can be operated under various pressures by the simple modification shown in Fig. 2. A glass tube with stopcock is inserted in one of the mercury pools. With the stopcock open, it is partly filled with mercury. A thick layer of melted sealing wax is then poured over the mercury pools and allowed to cool. A mixture of water glass, silica and barium sulphate would probably be preferable. Constrictions on the legs of the lamp will be unnecessary to this modified form.

After the arc is started as above described and the desired length obtained, the stopcock may be closed and various currents and voltages applied. This lamp is successfully operated with generator voltages of 125 to 150 volts through a bank of lights.

With the stopcock open the arc voltage is 50 to 118 volts, corresponding to 18-20 volts/cm gradient, the current being .75-1.4 amp.

SPECIAL ARTICLES

SAP FLOW AND PRESSURE IN TREES THE authors having been engaged in the study of movements of solutions in plants for several years arranged to collaborate in a series of experiments at the Desert Laboratory and at the Coastal Laboratory of the Carnegie Institution of Washington for a period of eight months in 1926. Professor Gilbert Smith joined us in some supplementary and anatomical studies for a few weeks. It seems advisable to present some of the results already obtained.

These support the theory of the upward movement of sap in trees in a cohesive column extending from the menisci in the walls of transpiring cells in leaves extending downward through dead wood cells and vessels and outward through the living cells of the root into the soil. The upward movement of water through such a system may continue at a diminished rate after the living cells at the upper and lower ends of the system are killed if the colloidal remains of the killed cells are not disturbed mechanically.

An examination of the assertions of Sir J. C. Bose that sap is pumped upward by pulsating action of living cortical cells has been made. Bose's claims as to the rate and mechanism of sap movements ignore well-established anatomical and mechanical facts, and are based upon imagined but impossible hydrostatic action of living cells. No single direct observation nor any measure of pulsatory action has ever been made, by Bose or any one else, yet his explanation of the ascent of sap is based on such an idea. It seems to be plainly evident to most beginners in botany that the drop of water applied to one smoothed end of a saturated branch is not identical with the drop appearing at the other end almost instantly, or that when water under pressure is turned into a hundred feet of filled garden hose the instantly resulting stream from the nozzle was made up of water that

had traversed the length of the hose, yet Bose's estimates of sap-flow are based on preposterous assumptions that erection of flagging leaves is due to water passing from the base of stems to these organs at rates of 70 mm per second or as much as 70 meters per hour.1

Bose's conclusion that the wood serves as a reservoir from which living cells draw water and pump it by pulsating action not through wood, but from protoplast to protoplast at the rates given would imply transfer through two to four hundred living cells per second is too fantastic to be the subject of any serious comment.

To ascribe rhythmic variations in galvanometer readings connected with probes pushed into cortical layers as due to hydrostatic pulsations is to throw aside all the safeguards of research. With Bose's suggestion that these pulsations may be the result of stimulation by friction of the roots with soil particles it is realized that the passage from pseudo-research to infantile fancies is an easy one. A sympathetic exposition of the Bose Institution and of the work of its director reprinted in The Garland (Calcutta) for May, 1926 (edited by S. M. Swaminathaiyer) includes the following passage: "For the mysteries of nature are probed in Sir Jagadish's institute not by study of libraries or by mechanical experiments, but primarily by communion with the unseen and the unknown. Inspiration, imagination, intuition, vision, this is an even more romantic touch."

The correctness of this characterization is attested by every page of Bose's book on the ascent of sap, which is utterly lacking in scientific significance. Such books appearing on the lists of scientific publications constitute a menace and danger to sound science.

Since the acceptance of Bose's work in America and since it has been widely proclaimed in the popular press of Great Britain, we are led to say that such recognition of Bose's work on ascent of sap and the nervous mechanism of plants has been confined to persons of non-scientific training, political propagandists and literary reviewers, whose capacity for judgment, motives and purposes may not be adequately discussed here.

Much attention has been given in our experiments of the past three years to the path of the upward movement of liquid in different types of woody stems and to the analysis of varying pressures which may be detected in the cortex, water-filled wood and gas mesh-work in the older wood. A comprehensive

1 Bose, J. C. "The Physiology of the Ascent of Sap.' " London, 1923.

2 This reaction has not been confirmed. See Dixon, H. H., "The Transpiration Stream," London, 1924.