thrift and justified by the widely prevalent but immoral theory that the institution may proceed "regardless of expense." THE HOOKER TELESCOPE One of the distinct, if relatively unimportant, misfortunes of the world war was the delay in testing the capacities of the 100-inch telescope named after Mr. John D. Hooker, of Los Angeles, who made the initial contribution toward the construction of this instrument thirteen years ago. It was substantially completed shortly before the United States became a participant in the conflict. About this time, also, the director of the Observatory became chairman of the National Research Council and he continued to give all his time to this governmental organization until May of this year. In the meantime, likewise, as already indicated, the staff of the observatory was preoccupied largely with military rather than with astronomical affairs. Hence, opportunity has only recently arrived for determination of the critical question whether this "largest telescope," which is 28 inches larger than its largest predecessor, and 40 inches larger than the highly successful 60inch instrument completed by the observatory in 1908, would meet expectations in optical capacity and practicability of operation. The construction of so large a telescope has been regarded as one of the hazardous undertakings of the institution. Its optical perfection depends on the stability of the glass used for its mirror; the stability of the latter depends in turn on the rigidity of its mountings; the requisites in both cases must take into account the elastic mobility of materials and the disturbing effects on them of temperature changes; and all these considerations must unite to secure a combination which is manageable. The problems in engineering thus presented have appealed very strongly to all parties interested in such constructions, perhaps almost as strongly as the astronomical possibilities anticipated from such an extensive addition to visual apparatus. But the director of the observatory now reports that the optical and the engineering difficulties The have been overcome and that the instrument under repeated tests has proved efficient quite beyond the conservative theoretical predictions of attainable capacities. on THE NON-MAGNETIC SHIP As related in the report of the preceding year, it was deemed expedient, in April, 1917, account of dangers to navigation, to suspend the cruise contemplated by the Department of Terrestrial Magnetism for additional surveys in the Atlantic Ocean by the ship Carnegie. As related also in that report, this ship was brought safely, by way of the Pacific Ocean and the Panama Canal, to the port of Washington, District of Columbia, arriving there June 10, 1918. She lay here until the spring of 1919, when it was decided to send her out again on her mission as soon as necessary repairs and alterations could be made. Of the alterations required, the most important was the adaptation of her engine for auxiliary propulsion to the use of gasolene as fuel. When the ship was launched, in 1909, it was easier to get anthracite coal than gasolene or other liquid fuel in remote parts of the world. Hence the engine was constructed to use gas derived from such coal by the so-called producer process. In the meantime, anthracite coal has become much less and gasolene much more accessible at distant seaports, and this circumstance has led to the noteworthy, and in these times expensive, but highly advantageous change here specially referred to. After delays which serve to emphasize the inefficiency of mankind under post-war conditions, on October 19, the Carnegie, under the command of Mr. J. P. Ault, put to sea from the Virginia Capes, on her sixth cruise, to comprise surveys in the Atlantic and Indian Oceans not yet adequately covered by previous circuits. PUBLICATIONS OF THE YEAR Of all branches of the institution the one least affected by the war is the Division of Publications. Although it has undergone some changes in staff and encountered the obstacles due to a rapid rise in the costs of printing and illustrations, its work has gone on without serious interruption; and the output of books for the year, as may be seen by reference to the detailed list given in a later section of this report, is rather greater than the average annual output for the past decade. Of the entire list of twenty-nine volumes issued, only two classes of them, selected mainly for the purpose of showing trends of progress, may be referred to here. The most elementary, the most essential, and hence the most widely used, if not esteemed, of the sciences is arithmetic. It is a fundamental requisite, in fact, of all exact knowledge. Ability to add, subtract, multiply, and divide affords probably the simplest test of capacity for correct thinking. Conversely, inability or indisposition to make use of these simple operations affords one of the surest tests of mental deficiency, as witnessed, for example, by numerous correspondents who are unable to or who refuse to apply these operations to the finances of the institution. But the familiar science of arithmetic lies at the foundation also of a much larger and a far more complex structure called the theory of numbers. This theory has been cultivated by many of the most acute thinkers of ancient and modern times. It has more points of contact with quantitative knowledge in general than any other theory except the theory of the differential and integral calculus. These two theories are complementary, the first dealing with discrete or discontinuous numbers and the second with fluent or continuous numbers. Naturally, a subject which has attracted the attention of nearly all of the great mathematicians of the past twenty centuries has accumulated a considerable history. The more elementary contributions of Euclid, Diophantus, and others of the Greek school; the extensions of Fermat, Pascal, Euler, Newton, Bernoulli and many others in the seventeenth and the eighteenth centuries; and the work of Lagrange, Laplace, Gauss, and their numerous contemporaries and successors of the nineteenth century, make up an aggregate which has stood hitherto in need of clear chronological tabulation and exposition. This laborious task was undertaken about ten years ago by a Research Association of the Institution, Professor Leonard E. Dickson, of the University of Chicago. A publication under the title "History of the Theory of Numbers" has resulted, and Volume I. (8vo, xii +486 pp.), devoted to divisibility and to primality of numbers, has appeared during the past year; and a second volume devoted to diophantine analysis is now in press. This work is remarkable for its condensation of statement. It contains more information per unit area than any other work issued thus far by the institution. It is remarkable also for the care taken by the author and by his collaborators to secure precision and correctness, a number of experts having assisted in the arduous labors of verification required during the process of printing. It is the object of science primarily to find answers to the question "How?" rather than to the question "Why?"; or, to seek to describe phenomena rather than to try to explain them. Words, however, constitute, in general, a rather imperfect medium for the communication of ideas, and as a consequence the intellectual world, like the political world, often finds itself involved in misunderstandings which lead to nothing better than that metaphorical and degenerate form of energy called the heat of controversy. Thus, about a half-century ago there arose, as we now see, a quite needlessly bitter discussion over the question whether and to what extent the phenomena of life may be traced back to the properties of matter with which they are obviously intimately associated. The new science of biology was just then arising and the limitations of its domain and the conditions of its existence and development were widely disputed, as is best shown probably by the lay sermon of Huxley delivered at Edinburgh November 8, 1868, "On the Physical Basis of Life." In this remarkable address Huxley defines, with prophetic clearness and completeness, the limitations and the conditions in question and these, as he defined them, are now generally admitted as essential to all fruitful inquiry. Moreover, the principles expounded by Huxley have been justified in amplest measure by the extraordinary progress since accomplished, not only in biology, but in all the physical sciences. It is good fortune for a research establishment to have been founded during the course of this progress and to be able to take part in it; and although the publications of the institution are not restricted to any domain of learning, a considerable number of them bear directly or indirectly on this profoundly interesting and increasingly important problem of "the physical basis of life." The past year has been unusually productive in this line, for no less than a dozen volumes have been added to the institution's series of contributions to evolution, heredity, and the application of thermodynamics to the interpretation of metabolism in man. These contributions are particularly noteworthy also for the extent to which cooperation has been required, since more than twenty authors and more than twice that number of collaborators are represented in the dozen volumes referred to. THE SIGNIFICANCE OF THE MEMBERS of Section I in attendance at the meeting last year will recall the address of the retiring vice-president and chairman of the section. This meeting offers a suitable opportunity to present at least one of the replies which such an address might be expected to call forth. Seventy per cent. of Mr. Dublin's paper was occupied with statistics, and these we may accept as coming from an expert statistician. It is the remaining thirty per cent.embodying the author's view of the significance of the declining birth-rate-that invites attention. To begin with, I hardly need point out the necessity of recognizing the prevalence of multiple and compound causes in all fields of social phenomena. When a compound cause has been disentangled from a mass of observations its individual factors must be care 1 Read before Section I (Social and Economic Science) of the American Association for the Advancement of Science, Baltimore, December 27, 1918. fully weighted in order to give proper prominence to the chief one. Mr. Dublin arraigns the women and their education for the declining birth-rate. In so doing he involves himself in a significant concession; and one wonders how, with so much of a clue, he has failed to perceive the true interpretation of the social feature which he deplores. He has fixed his attention on very minor and limited causes only to lose sight of the great generic cause. For we are to-day in the midst of a revolution quite unparalleled in the history of the human race whether it be viewed as regards the number of persons concerned, or the length of its preparatory prelude, or the importance of the consequences which will undoubtedly follow it. I refer to the movement connected with the discovery that women, in spite of being females, are primarily human beings, with the same desires for freedom and self-direction, the same ranges in tastes and abilities and ambitions, that men have. discovery is due to woman's recently acquired opportunity for knowledge and opportunity for economic self-dependence. These opportunities themselves seem to be involved first as effects and then as causes in modern human progress. The evolution of societycivilization itself-had proceeded as far as it could, with the archaic status of woman unmodified. This Folklore and literature from earliest times to very recent days have been charged with positive expressions of the place and duty of the female. Radical writers and conservative ones alike, teachers, philosophers, statesmen and poets, have with few exceptions-been agreed that that place was home and that duty the care of the home and the rearing of children. Very naturally all schemes of government and all systems of theology have been in harmony with this popular conviction. To cook a thousand meals a year, to make beds and wash dishes a thousand times a year, to bear children-always to bear children-in meekness and resignation, has been held to be the woman's lot as ordered by Providence or at least by Nature. What else could a normal woman want to do? If reiteration could save a doctrine or confer the attribute of truth this doctrine would not now be moving to join its companion superstitions: Special Creation and the Fall of Man. The savage with his savage job of hunting and fighting made the inferences that might be expected from a primitive mind regarding the creature who staid at home to cook his food and care for his child: one who could not-or at least did not-fight was inferior. The reasoning of post-savage and post-barbarous peoples is an extraordinary mass of testimony to the slowness with which the human mind has advanced to scientific aptitude. Philosophers, theologians and statesmen-no less than common persons -have failed to perceive that no conclusions based on observations of unfree human subjects can safely be drawn regarding what is normal in those subjects. Failure to recognize this principle accounts for the surprise, the dismay and the disapproval upon witnessing among free woman what is apparently most unnormal behavior; that is, behavior inconsistent with the normal or type-form as it had been understood. In the United States, as late as 1850, women-being without other means of securing food, clothing and shelter-married on terms not of their own making. They bore children according to the pleasure of those whom they were to obey and in recognition of a dogma of theology which they were taught to hold as divinely endorsed. For, lacking knowledge, women were no more free in mind than they were in body lacking economic independence. This type of woman has practically disappeared below the historical horizon-succeeded by a multitude of women of affairs, in gainful occupations, in the activities of business, philanthropy, education, professions and in concerns that require the highest order of organizing and administrative ability-women who offer no apology for their choices and no defense of their activities. Now, the most noticeable consequence of the new freedom is that each woman is deciding for herself whether she will marry or not. And in case she does marry, the deciding vote as to the number of children to follow is likely to rest with her. The woman of to-day will herself determine what her duty is in the case. We may reason with our equals or appeal to them; but for one person to tell another grown-up person his duty, or for one class of persons to dictate the duties of another class, seems now to be unsustained by ethical courtesy. Justice has reached the point of insisting that as regards bearing many or any children a woman must be free to decide-free from the coercion of government, or religion, or public opinion, or a disordered conscience. That "revolution" is not too strong a word to mark what has taken place in two incomplete decades of the twentieth century is well indicated by comparing the war-time position of women in the past with that of the present. The lady of the nineteenth century and all preceding ones waited and wept at home and prayed for her lord's safe return from the wars. To-day history takes into her keeping the story of the multiple Entente of women who helped to win the Great War. The sudden need that women should come out of the home and lend a hand in a hundred ways has led to an unexpected and perhaps unwelcome proof of what they will usually do as free persons. No doubt there are those who find consolation in the thought that women's war activities have been a spasmodic though commendable expression of patriotism, a temporary estrangement from their true work and, the war over, they will return to their "normal" place: the home. It may readily one be admitted that the new freedom is too new to permit of immediate conclusions. Sociol ogy no less than geology or physiology or any other science requires us to suspend judg ment. All that can be asked on the hand, all that need be granted on the other, call is that in the great laboratory which we human society the class investigated, women, shall be free. A provisional judg ment is that while many women will probably prefer to devote themselves to domestic activities, many others will be equally inclined and resolved-to occupy themselves with the varied pursuits which have hitherto the been claimed by men alone. The statistics of the Census of 1920 will contribute much to the discussion. Meanwhile it must be disconcerting to reactionary persons to observe how many young women are disposed to do the very thing for which young men are commended; namely, to select a line of work and carry it through to success. But the declining birth-rate. If n is the number of births per thousand per year and n' the number of deaths per thousand per year of children, say under one year of age, n-n' is the effective birth-rate. Obviously this can be raised by increasing n or by diminishing n'. To increase n has been the way of barbarism. "What if the children do die; the woman can bear plenty more." This is not the sentiment of some distant past age; for, as Francis Galton remarks, men were barbarous but yesterday. The method of the new civilization is to decrease n'. Up to last July (1918) the Federal Children's Bureau had weighed and measured approximately six million children under six years of age. A large number were were found to be undernourished; many others were victims of diseases easily remedied by proper medical attention. Under the auspices of this bureau nation-wide plans are developing to provide public health nurses, better hospital care and the conservation of milk for children. It appears also that really effective means for saving the young children involves care of the mother not only after the child's birth but also months before. "Save 100,000 of the 300,000 children that now die annually under one year of age!" is not the slogan of a few sentimental philanthropists; it is the purpose of the national government. This federal bureau further reports that 15,000 women die annually in the United States from childbirth; and it declares that of this total most of the deaths are preventable because due to ignorance and improper care. Nothing in this world has been so cheap as child-life except mother-life. But I now squarely challenge Mr. Dublin's fundamental assumption that a declining birth-rate is an evil. What reason does he give, what reason has anybody given, why the hither and the uttermost parts of North America say, should forthwith be populated as rapidly and as densely as may be even by elect stock. Why should the natural forests be so hurriedly worked into lumber and the country's non-restorable natural resourcescoal, petroleum, gas and others-be exploited to the exhaustion point? Has the United States any grounds for felicitating herself on the fact that she is burning coal at the rate of 600,000,000 tons per year? And how many years may she expect to continue such selffelicitations? It is the crudest form of collective selfishness for any one generation to act as if it had a final lien on the earth when at best it is only a temporary tenant, in honor bound by the highest racial ethics to consider the interests of those who follow: the peoples of distant centuries. This generation more than any which has preceded it seems bent on bequeathing an impoverished domain to its "heirs and assigns forever." "Few men really care what happens to posterity." Are Your vice-chairman's protest against any decrease in the birth-rate meets rebuke also in the condition of the congested points where most of the increase in population is to find its home: the city. Are the city's streets— all of her streets-clean and attractive? her homes-all of her homes-sunny and sanitary? At what age do her children leave the public schools, and why do they leave? What are the hours and wages of young women in her laundries, candy-shops, stores, restaurants and factories? Are her women citizens no longer discriminated against as political outlaws? Has the city figured out a minimum of subsistence, of health, of education, of leisure, for all of her citizens? Until these questions are satisfactorily answered the "socially and economically efficient class " may well address itself to the practical task of bettering the conditions of human living rather than to an effort to state the population of the city in six figures instead of five. Mr. Dublin's theory that the country will be saved if the afore-mentioned "socially and economically efficient" will only marry and raise large families runs counter to facts, for facts show that permanent betterment can |