row, more than half this distance over territory never seen by human beings, thus making a great inroad into the largest unexplored area north of the equator. They had flown 550 miles and had almost completed the outward flight when engine trouble developed and they had to make a forced landing.

This was a deciding moment in Arctic aviation, for there have been two theories as to the safety of landing on the frozen sea. One school has held that there are scarcely any safe landing places on the moving Arctic pack, and the other school, to which Wilkins himself belonged, that landings are so numerous that there seldom is a five-mile stretch without a fairly good one. (Byrd has not agreed with Wilkins but has taken a position between the two theories-nearer to the first.)

In less than five miles they did find a place that looked good to Wilkins. He gave the instructions and Eielson made a perfect landing on ice which turned out to be about three and a half feet thick when Wilkins, a few minutes later, made the holes in it which were necessary to take a sonic sounding. He took two soundings and found the ocean there to be about three miles deep, which makes it very unlikely that any land can exist in this direction, for their flight, if continued far enough in the same direction, would have taken them near where Nansen years ago in the Fram took similar soundings. This sounding was a verdict as decisive in oceanography as the landing had been in aviation. It made it extremely probable that those are wrong who, following Harris, have maintained that there is a great unknown land in the Arctic, and that those are right who, following Nansen, have argued that it is in the main a deep sea.

While Wilkins was doing this sounding, Eielson tinkered with the engine. In two hours they were in the air again, flying back towards land because a strong offshore wind had blown up, making it probable that the gasoline would fail to take them ashore even

now.

After about 10 minutes' flight, the engine gave trouble once more. There was a second forced landing and a second test of the question of landing places. Again Wilkins picked out a likely site, and again Eielson made a perfect landing. This time both worked on the engine and made a better job, so that when they took off a second time the machine hummed along smoothly. But clouds gathered and the wind. stiffened continually, so that they presently realized that they were unlikely to get ashore. It was after sundown, with heavy clouds in a thick blizzard, when the engine stopped suddenly, out of gas. This time they could not see anything and the landing was pure luck. As a matter of fact, instead of striking a very smooth expanse, as might have happened by chance,

they struck a very rough one, and it was as if by a miracle that they made a landing safe for themselves, although it crippled their plane. But that crippling was of no practical consequence when they were out of gas anyway.

It now developed that Eielson had frozen his fingers severely when tinkering barehanded with metal tools on the metal of the engine at 30° below zero in a strong wind. Wilkins asked him later why he had not taken time off to warm his hands occasionally and keep them from freezing, to which Eielson replied that he "preferred losing a few fingers to losing both arms and legs and what they were fastened to."

Wilkins and Eielson spent five days on the floe where they landed and during that time another strange thing happened, for the ice in this quarter is usually drifting west and Wilkins noted in his diary that they would therefore probably have to land in Wrangel Island, but instead it now drifted rapidly east, and when they had broken up the wooden parts of the plane and made them into sledges, they found themselves 100 miles east of Barrow instead of several hundred miles west (as might easily have been the case had the drift been as usual) and 70 miles from shore, or 30 miles nearer than when they had been forced down.

Wilkins reports laconically about the journey ashore that they slept comfortably at night in the snowhouses which they built, that they saw plenty of game and could have secured seals for food and fuel indefinitely had they needed it, but that they had with them enough biscuits and chocolate to eat and enough engine oil to burn. They were hurrying for two chief reasonsbecause Eielson's hand had been so severely frozen that an amputation of fingers seemed necessary, and because they wanted to get back to Barrow so they could do more flying with their other planes before the summer fogs commenced. This hurry made them take possibly unnecessary chances on thin ice, and in consequence Wilkins fell through on one occasion, getting wet to the armpits at a temperature of 30° below zero (62° Fahrenheit below freezing). His only comment is that he knew his other garments would dry better on his body than otherwise and that he had no change of clothing anyway, but that he did have a change of socks and boots which he made promptly in the lee of an ice ridge.

After several days' travel the ice became so rough that the improvised sledge could not be pulled over it. Wilkins recognized that this was the shore ice and that it was therefore safe to leave the sledge behind. So they took the more important baggage as packs on their backs and scrambled over ridges of slippery ice where the crevices between the broken pieces were filled with snow so soft that they had to crawl several

miles in the sense that they would keep their hands on pieces ahead while their knees and feet were on the pieces they were just leaving.

Their astronomical observations proved to have been correct and their course took them directly into the Eskimo settlement at Beechy Point, where there is a trading station. From here they made their way to Barrow, where Eielson's little finger was amputated at the mission hospital. The other fingers were saved. His deep soundings having made it improbable that there is undiscovered land in the 600,000-mile section to the northwest of Barrow, Wilkins now plans to cross the 300,000-mile section to the northeast, where there is the best remaining chance of land. He expects to fly diagonally through the middle of it from Barrow to 84° N. Lat. and 100° W. Long. and thence to Ellesmere Island, coming down when they have to or possibly flying nearly, if not quite, all the way to Etah.

If the plane comes down anywhere on this route, Wilkins expects his party to live by hunting seals and make their way to the nearest inhabited land. This will be Alaska if they have hard luck and come down soon. It may be any of the Canadian islands, according to how far they succeed in flying; it will be Etah, northwest Greenland, if everything goes like clockwork. The outcome of the adventure can not be known before perhaps midsummer when the Danish trading ships go up to Etah or the Canadian government ships go to Ellesmere Island. If nothing is heard then or before that time, it will mean either a fatal landing or a successful landing at a distance from which the party are returning, building snowhouses in winter, using skin tents in summer and living on sea game.

Wilkins estimates the maximum

time necessary for such a return on foot will be two years. We wish him luck with his great adventure. RICHARD E. BYRD, VILHJALMUR STEFANSSON

EFFECT OF HIGH VOLTAGES ON TANTALUM ANODES

DURING some recent work with high voltages upon metal electrodes I have found that tantalum exhibits some very unusual phenomena when used as a positive electrode in certain electrolytes. Very brilliantly colored films are formed on the metal in the following order: violet, reddish purple, indigo, light blue, green gold, light yellow and finally gray. The colors were produced in succession by increasing the voltage so that any one of the above colors may be obtained by shutting off the current at the proper time. The films form just before the electrode begins to emit light and the highly colored ones disappear when ting ing sparks appear on the

THE Fisheries Department of Ottawa has recently received from the Biological Board of Canada a memorandum of the losses in four thousand speckled trout fry after distribution in Forbes brook, Prince Edward Island, Canada, for three months (JulyOctober) of 1926. Mr. H. C. White, B.A., was investigator for the Board for 1926 as well as for the three previous summers. The supervising investigator was Dr. A. G. Huntsman.

The plan selected for the experiments provided that a part of the upper stretch of the brook should be subdivided into four equal sections of ten rods each. Each section was separated from the other by transverse wire screens which were fry tight. Each section was seined completely free from enemy and competition fish before an experiment began, except as mentioned below.

The object of three of the experiments was to ascertain whether (1) adult trout (any over one year old) or (2) birds, or (3) stickleback caused the greatest loss among fry after distribution. (4) The object in the fourth experiment was to determine the total loss from all natural causes combined.

Section No. 1 was left in its natural condition and planted with 1,000 fry. At the end of three months, 712 of them were missing. This compares with seventy-three per cent., which was the loss in 1925 near the same place. Of 38 adult trout in this section in the spring, only 19 survived until October.

Section No. 2. The adult trout were removed and it was screened overhead from birds. 209 stickleback were confined with 1,000 fry. Out of the 1,000 fry deposited in it, only 504 survived at the end of three months.

Section No. 3. Birds were screened from this section and all fish seined except 32 adult trout. Here only 361 fry survived out of 1,000.

Section No. 4. Stickleback and adult trout were removed from this section; but it was left exposed to birds. Out of 1,000 fry planted in the spring, only 435 were found alive in autumn.

From the foregoing experiments it would appear that stickleback alone caused the death directly or indirectly of 49 per cent. of the fry; birds, 57 per cent.; adult trout 64 per cent.; and all natural enemies combined 71 per cent.

Summarizing our results for the past four summers: In 1923, the loss of trout fry in southwestern Ontario was 962 per cent.; in 1924 it was 98 per cent., same place; in 1925, it was 73 per cent.; and in 1926 it was 71 per cent. These two latter on Forbes brook, Prince Edward Island, Canada.

It is quite possible that a portion of the losses may be due to cannibalism among the fry themselves; but this would not alter the total losses as given above.

KINGSTON, ONTARIO, CANADA

A. P. KNIGHT

THE NEED FOR DEFINITELY INDICATING NEW SYNONYMY AND NEW COMBINATIONS IN TAXONOMY

RECENTLY Dr. Schramm, of Biological Abstracts, requested me to serve as a member of a committee to advise the organization publishing Biological Abstracts in regard to a number of policies on indexing information from taxonomic papers. One of these questions dealt with the indexing of synonymy and another with the indexing of new combinations of generic and specific names.

It is very important that the working taxonomist should know when a given species is transferred from one genus to another, and it is equally important that he should know when a species name has been suppressed as a synonym of some previously described species. It is the aim of the founders of Biological Abstracts to furnish such essential information to students of taxonomy. They have found it very difficult to tell from many papers whether synonymy as indicated in the paper is new or has been previously recorded. They have also found it difficult to determine when species are transferred for the first time from one genus to another. This is especially true for papers dealing with taxonomic zoology.

It therefore seems advisable to present for the discussion of taxonomie zoologists the desirability of determining some way of indicating in their papers when new synonymy is proposed and when new combinations of generic and specific names are employed. In many of the recent extensive revisionary papers, long specific bibliographies have been given with no indications as to whether any of the synonymy is new. It is suggested that an easy way to overcome this

would be to write in parentheses the words "new synonymy," or some abbreviation thereof, after each reference to a newly published synonym.

The labeling of new combinations or transfers of species from one genus to another forms a more decided digression from the practice commonly used by zoologists, and especially entomologists; but it is believed that if taxonomic workers would place the words "new combination," or some abbreviation thereof, in parentheses after each such transfer or new combination, it would greatly expedite the work of abstractors and catalogers, and to no small degree assist their colleagues.

Botanists have been much more careful and definite in indicating and cataloging all new combinations. I think it is time for the zoologists to take a lesson from the botanists and label their new combinations. It seems to me equally important that the botanists and zoologists agree to indicate in some clear manner all new synonymy.

BUREAU OF ENTOMOLOGY, WASHINGTON, D. C.

S. A. ROHWER

SURFACE TENSION METHODS ATTENTION should be called to the misapplication of a quotation of Lenard in SCIENCE for March 18, 1927. Lenard states that the straight wire method, as a tearing off method, "as opposed to the ring method" (in Gegensatz zur Ring- oder gar Scheibform des Abreisskörpers) gives the accurate results to which Dr. du Noüy refers. Lenard by no means considers the ring method on equal terms with his own "tearing off method." Lenard's method is not entirely recent and was approved as a substitute for the ring method several years ago. (Cf. Jour. Phys. Chem. 1925, 897.)

VANDERBILT MEDICAL SCHOOL, NASHVILLE, TENNESSEE

J. M. JOHLIN

SCIENTIFIC BOOKS

The Fauna of British India, including Ceylon and Burma. Hirudinea. By W. A. HARDING and J. PERCY MOORE. London: Taylor and Francis, March, 1927.

THE new volume of the fauna of British India. devoted to leeches, is perhaps the most exhaustive and certainly one of the most interesting of the whole series. As there are only forty-six species to be discussed, it is possible in about three hundred pages to go into a great deal of detail about structure, habitat and relationship to human affairs. The editor, Sir Arthur E. Shipley, contributes a readable historical

preface, in which he relates the various opinions of ancient times concerning leeches. Professor J. Percy Moore has written a chapter on segmentation of the Hirudinea, and has worked up the families Erpobdellidae and Hirudidae, including the familiar large leeches of the type used in medicine, and the dreaded blood-sucking land leeches. Mr. W. A. Harding describes the Ichthyobdellidae and Glossiphonidae, which include just half of the species in the fauna. Among the Glossiphonidae are Glossiphonia complanata and Helobdella stagnalis, also found in North America. Most remarkable is the account of the ferocious land leeches of the genus Haemadipsa. Although these have been discussed by many writers, there is much still to be learned concerning them. In their local variations, with the formation of distinctive subspecies or closely related species, they are said to differ from the aquatic leeches, and follow more nearly the manner of evolution of the land snails. Moreover, several of the color-varieties are associated with land planarians which are similarly colored, suggesting mimicry. Altogether, the book is much more than a local fauna, and will rank as a standard work, indispensable to all who have occasion to study leeches.

UNIVERSITY OF COLORADO

T. D. A. CoCKERELL

Vorgeschichtliches Jahrbuch für die Gesellschaft für vorgeschichtliche Forschung. Herausgegeben von MAX EBERT. Band II: Bibliographie des Jahres 1925 mit sechs Tafeln und einer Abbildung im Text. Berlin und Leipzig. Walter de Gruyter und Co., 1926.

THE Gesellschaft für vorgeschichtliche Forschung, founded in 1925, has for its object the advancement of Prehistory in all its fields. Its managing committee consists of Max Ebert (chairman), Königsberg; O. Almgren, Upsala; G. Karo, Halle; B. Meissner, Berlin; H. Obermaier, Madrid; H. Ranke, Heidelberg.

The 344 pages of the Prehistoric Year Book form a fair criterion of the ever-increasing activity in the general field of prehistory. All but seventy-eight pages are given over to bibliography, only the more important references being accompanied by a review consisting of one or at the most a few paragraphs. This "review" of the literature comes under four heads: A, Europe-General; B, Paleolithic and Mesolithie; C, Europe-Neolithic and later periods; D, Egypt; E, Palestine and Syria; F, the Near East. The other features of the volume are: (1) an illustrated article on the excavation of prehistoric fortifications (twenty-two pages), (2) news of a scientific

and personal nature, and (3) the index, consisting of twenty-eight pages. This is an Old World Year Book, as will be seen from the table of contents. That such a large and creditable volume is annually possible is a striking commentary on the rapidity with which our knowledge of Old World prehistory is expanding; it fully justifies the existence of our American School of Prehistoric Research, founded in 1921 in order that American students might the more readily obtain first-hand knowledge of Old World prehistoric records as well as to have a part in recovering and interpreting them.

The NH, catalyst consists of a fused mixture of pure artificial magnetite to which about 1 per cent. of aluminum oxide and 1 per cent. of an alkali oxide, usually potassium, has been added in the fusion process. The mixtures investigated included an unpromoted iron, an iron promoted with aluminum and potassium oxides, and a tin poisoned catalyst.

The surface upon which the decomposition took place was prepared by fusing the mixture of the finely powdered granules to a twisted platinum strip.2 It was found that the coating process could be carried on through a range in temperature of from about 300° C. to 1,200° C. Very uniform coatings of the desired thickness of the mixture can be obtained so that the temperature of the coating was very uniform and easily controlled by varying the current through the strip. The chemical activity of these surfaces after a thorough reduction depended upon whether the catalyst mixture was coated in the reduced or metallic form, or in the unreduced or oxide form, and the temperature at which the coating takes place. Thus the rate of decomposition of NH, on a given catalyst mixture at a given temperature was found to vary four fold. The coated strip was mounted in a two liter decomposition chamber, and the increase in pressure with time, for a given temperature, was re

1 Preliminary results on the use of this method for the

testings of catalysts was presented at the Jubilee Meetings of the American Chemical Society at Philadelphia in September, 1926.

2 Jour. Phys. Chem., 30, 525, 1926; Jour. Franklin Institute, May, 1927.

corded. By making the hot strip an arm of a wheatstone bridge arrangement, the temperature of the hot surface could be kept very constant through the decomposition test. The temperature setting was made from a calibration curve obtained from the resistance of the bridge settings and temperature of the surfaces, as determined by an optical pyrometer.

From the time for one half of the NH, to decompose on the surface for various temperatures the value of E in Arrhenius equation-rate of chemical

E

RT

change = Ae was determined. E is the observed heat of activation determined from the slope of the straight line for which the abscissa is the reciprocal of the absolute temperature and the ordinate is the logarithm of the time for one half of the NH, to decompose. The resulting value of E has been determined from a 200 degree change in temperature, for temperatures between 475° to 750° C. depending upon the activity of the catalyst. From the nature of the reaction, and relatively small effects of the products of the reaction on the initial rate of decomposition, E may not be far from the true heat of activation or the measure of the molecular stability on the surface.

The results of these tests give values of E for the various catalysts from 38,000 to 42,000 calories per gram molecule, where the difference in catalytic activity of the various mixtures for a given temperature was as much as eighteen fold, as measured by the rate of the decomposition of NH..

It would seem, then, that the effect of a promoter or poison on the catalysis is to increase or decrease respectively the active surface or parts of the surface where decomposition takes place.

These results on the effect of a promoter or poison are in agreement with the idea of an extension of the active surface arrived at from experiments on the synthesis of NH..

The more active catalysts for the decomposition were also the best catalysts for the synthesis; likewise the poor or poisoned catalysts for the synthesis were found to be relatively poor for the decomposition.

Thus from these experiments we may conclude: (1) That the primary effect of promoters on the iron catalysts is to increase the number of atoms upon which decomposition takes place.

(2) That the effects of heat treatment and poisoning on the catalyst is to decrease the number of atoms upon which decomposition takes place.

(3) That neither poisoning, heat treatment nor promoter action sufficiently alters the quality or nature of the atoms upon which the reaction takes place to cause an appreciable change in E, the heat of activation.

It is also interesting to note that if further experiments now in progress in the laboratory should confirm our belief that this 40,000 calories represents closely the true heat of activation for the decomposition of NH, on the iron catalyst, and that our value corresponds to the 39,000 calories found by Hinshelwood for the heat of activation for the decomposition of NH, on tungsten, and to the true heat of activation of NH, on platinum calculated by H. S. Taylor to be not less than 43,000, it would indicate that the true heat of activation may be a function only of the reacting gas and not of the catalyst present. C. H. KUNSMAN FIXED NITROGEN RESEARCH LABORATORY, BUREAU OF SOILS,

U. S. DEPARTMENT OF AGRICULTURE

A CRITICAL FACTOR IN THE EXISTENCE OF SOUTHWESTERN GAME BIRDS COMPLAINT is continually made, on the part of both sportsmen and bird lovers, that despite all sorts of protective measures the wild quail in many districts of California are disappearing. Even in localities which have been set aside under public or private auspices as game refuges, and where prohibition of shooting is enforced, this diminishment in the numbers of quail continues to be reported.

Sportsmen are prone to ascribe the disappearance of game birds, where living conditions otherwise remain seemingly favorable, to the activities of socalled "vermin" of various kinds, giving little weight to the fact that in most parts of the country said "vermin" (hawks, owls, foxes, wildcats, etc.) have also become greatly depleted since the time when the original balance prevailed.

In casting about for some cause to hold responsible for the diminishment noted in such birds as the California quail, the student of natural history may properly proceed to check off the various factors known by him to bear importantly upon the existence of the species in question, one by one, and see what may be left. On certain brush-land areas in southern California, familiar to the writer now and thirty years ago, I am quite sure of the following conditions: (a) The food supply remains, in so far as I can see, in both kind and amount about the same; (b) shelter, that is, "cover," is of quite the same character and quantity as formerly; (e) natural enemies are most certainly fewer in individual numbers and hence levy less of a draft on the quail population than formerly; (d) hunting by man has in large measure been done away with on the particular territories in question.

Sportsmen and some biologists have stressed the probability of some disease having invaded the quail population. Upon this question I have nothing worth