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Astronomical Society of the Pacific 
 ADDRESS 
 
 OF 
 
 WILLIAM M. PIERSON 
 
 Retiring President of the Society 
 AT THE 
 
 KOTJRTH ANNUAL MEETING 
 
 San Francisco, March 26th, 1892 
 
ADDRESS OF THE RETIRING PRESIDENT OF THE 
 
 SOCIETY, AT THE FOURTH ANNUAL 
 
 MEETING, March 26th, 1892. 
 
 By William M. Pierson. 
 
 A review of the three years' life of this Society ought to be 
 full of encouragement to all of us. Too often the expectations 
 of the earlier members of a Society, particularly a scientific one, 
 are not realized. Those who join for mutual improvement in the 
 science do not immediately realize their hopes, and those who 
 unite for the love of the novel, frequently fail to have their curi- 
 osity gratified. These naturally fall away through the loss of 
 their original interest. But the reverse has been the rule with 
 this organization. The Society has steadily advanced from its 
 feeble beginning, and to-day finds itself a permanent, a practical 
 and a properous organization. 
 
 Its first meeting had a record of forty members on the roll. 
 At the end of the first year its membership had increased to one 
 hundred and ninety-two. Its second year closed with a list of 
 three hundred and sixty, and its third year, now finished, dis- 
 closes a total of four hundred and thirty-two, of whom three 
 hundred and eighty-one are active subscribing members, and 
 fifty-one life members. 
 
 Considering that the Society is located in a district of the 
 United States peopled by less than two millions of inhabitants, 
 among whom, aside from public observatories, probably not a 
 dozen are possessed of any telescopic appliances, it is indeed 
 remarkable that the Society has on its roll over two hundred 
 local members, all of whom take or feel an active interest in its 
 progress. Indeed, considering the environment of the Society, 
 
it may well be doubted if any purely scientific organization has 
 ever met with such a degree of prosperity. 
 
 Remarkable, however, as this growth has been, it ought to be 
 the aim of each of us to stimulate it still farther. The greater the 
 Society, the more widespread its influence and the more valuable 
 its contributions to the cause of science. It has been the aim of 
 the officers of the Society to maintain its publications at the high- 
 est standard of excellence. But they constitute the larger part of 
 its expenses. Many scientific papers of great value, many details 
 of discoveries made by the great refractor of the Lick Observa- 
 tory, and many reproductions of exquisite celestial photographs 
 could and ought to be published did our means justify it. We 
 all can aid in the accomplishment of this desirable result. If each 
 of us would introduce one new member during the coming year, 
 the Society would be enabled to greatly extend its sphere of use- 
 fulness and its advantages to science and to ourselves. 
 
 From the Treasurer's report you will learn that the Society is 
 on a sound financial footing. The permanent funds, those which 
 we owe to the munificence of Mr. Alexander Montgomery 
 for the maintainance of the Alexander Montgomery Library, 
 and to Mr. Joseph A. Donohoe for the Comet- Medal, are well 
 and securely invested. 
 
 The Society owes a heavy debt of gratitude to its Publication 
 Committee, and particularly to its chairman. Professor Holden, 
 for its and his labors in editing the Publications of the Society. 
 It is a class of labor particularly onerous and exacting, performed 
 without compensation and of a quality that is wholly unexcep- 
 tionable. 
 
 In retiring from the Presidency, I desire to extend to all the 
 officers of the Society my sincere thanks for their hearty assist- 
 ance and courtesy during my term of office, and to the members 
 for their uniform kindness and good will. 
 
 The past year has developed a greatly increased interest in 
 astronomical research. The formation of new sections of this 
 Society, the improvement and enlargement of astronomical peri- 
 odicals, the establishment of new observatories, both public and 
 private, the system of university extension, and above all the dis- 
 semination of celestial discoveries in the public press — that most 
 accessible of all educators — have given a marked impetus to the 
 study of Astronomy. The proximity to us of the Lick Observatory 
 with its grand instrumental power and skillful staff of observers, 
 
has served to make its revelations easily and immediately attain- 
 able to the public, and largely increased the general interest in 
 the science. 
 
 This increasing interest in astronomical research has not been 
 limited to intellectual sympathy alone, but has also assumed the 
 tangible and valuable form of financial aid. I take great pleasure 
 in announcing that Mrs. Phcebe Hearst, the widow of Senator 
 Hearst, of our State, is about to found several Fellowships in 
 Astronomy at the Lick Observatory, and to provide a permanent 
 fund, the interest of which is to be used to promote the scientific 
 work of that institution. 
 
 While the collection and dissemination of scientific discoveries 
 are the principal objects of the Society, it fulfils, nevertheless, 
 another and equally valuable purpose, the instruction of those of 
 us who are merely amateurs: In a wide sense the Society is a 
 school. And yet a school wherein we may all to a greater or 
 less extent be tutors as well as pupils. While the professional as- 
 tronomer, in possession as he is of the most powerful and refined 
 instruments and methods of observation, can and does contribute 
 vastly more than others to the general stock of scientific knowl- 
 edge, yet there are none so meagerly supplied with those facilities 
 who cannot furnish something — if not original discovery, yet that 
 which may supplement and confirm it. 
 
 The difficulty with those of us who are amateurs, or at least 
 the difficulty that I, as a novice, first encountered in astronomy, 
 was that, after understanding the general outlines of its descriptive 
 department, I was at a loss where to begin or what to do in the 
 way of observation. The temptation to wander over the sky with 
 a telescope is almost irresistible, but as a rule nothing is so profit- 
 less. It hardly gratifies the curiosity, for the reason that one is 
 ever lamenting that he does not see more than his lens is capable 
 of revealing. 
 
 I shall be pardoned, I hope, by the professional astronomers, 
 who constitute so large and invaluable a part of our Society, if as 
 an amateur I make some brief suggestions in this connection to its 
 amateur members. I make them with the more freedom because, 
 as my predecessor very properly said, ' ' We should not forget 
 that we are a society of amateurs." They are the result of my 
 own experience, and have not been without value. In the hope 
 that they may be of some service to others, let me state them. 
 
 Specializing, particularly in Astronomy, is indispensable to any 
 
success by the amateur. First of all, have some Inquiry, some 
 object in view. That is the great charm of all scientific investi- 
 gation, because in pursuing it you can note your progress — an 
 invaluable stimulus to study. If you are provided with optical 
 instruments, devote yourself to some particular field, some par- 
 ticular planet, or, if you have the time for day work — the Sun. 
 
 For example, select a region of the sky, say from one to five 
 degrees square, the area being in inverse proportion to the aper- 
 ture of your telescope. If the portion you decide on be in the 
 vicinity of the equator or ecliptic, select two at opposite points of 
 the heavens — one for Summer and the other for Winter observa- 
 tion. If near the pole, one would suffice, as it would be visible 
 to you the year round. Make these districts of the sky your 
 special field of observation. Consider that your exclusive domain. 
 Make it a point to observe it on every observing night, whatever 
 else you look at. Use the lowest power of your telescope in 
 sweeping over this field. Familiarize yourself with every object in 
 that region within reach of your lens. Note the magnitudes of 
 all the stars within it, their colors, their arrangement in space, 
 their distances from each other, the presence or absence of any 
 nebulous appearances. Indentify every star you can by the aid of 
 your star maps; know them by their names or their catalogue 
 numbers. If you have the means of measuring their distances 
 from each other, do so; if not make eye estimates. A very little 
 practice will enable one to make fair eye estimates of distances. 
 Ascertain the actual angular distances of such stars within your 
 field as are given in your star maps or star catalogues, and com- 
 pare them with the visual angle between them as seen in your 
 telescope under a given magnifying power, and you will soon be 
 able by comparison to determine with a fair degree of approxima- 
 tion the distances of other stars whose actual position you may 
 not be able to find otherwise. 
 
 Above all things, make notes at once of what you observe, 
 with all the details possible. Trust nothing to your memory. 
 An accurate observation of a single phenomenon may be of great 
 importance. No fact is without value, and your observation may 
 at some time fit into a series which would be otherwise incom- 
 plete. Remember that celestial phenomena occur but once, and 
 you may happen to be the only person to have observed that 
 one. 
 
 If you will do this, it may be your fortune to be the first to 
 
detect a comet, or, if your field be not too far from the ecliptic, 
 a minor planet; for the motion of the latter is very marked with 
 reference to the fixed stars, and that of the former, unless ap- 
 proaching directly in the line of sight, is quite conspicuous. Or 
 mayhap you may be the lucky discoverer of a new star, always 
 a matter of absorbing interest. And if you succeed in neither, 
 you will still have the satisfaction of knowing more about the par- 
 ticular section of the sky which you have made your own, than 
 any one else who has not done the same. 
 
 And so, if you select a planet, or our own satellite, or the Sun, 
 make it your special study, whatever else you may choose to ex- 
 amine. Regard that as your specialty. Scrutinize the changes 
 in its appearance — read all there is to be found about it — examine 
 it with reference to the researches of others, and compare them 
 with your own investigations, and again, — make notes of all you 
 observe. 
 
 It is remarkable how much more the professional astronomer 
 can see than the novice, even with the same telescope. And yet 
 it is for the very reason that I have given. The veteran is familiar 
 by long study with the details of the special object of his examina- 
 tion, and therefore detects at once the changes, if any, which have 
 occurred in its appearance. That is the reason why it has been 
 so justly said that astronomical observations depend not so much 
 on the power of the telescope as on the man at the small end 
 of it. 
 
 The ardor of the amateur is, however, frequently cooled by the 
 feeling that no results attend his labors. He makes no discov- 
 eries; he finds himself treading only in the beaten track of others; 
 his progress in science is unmarked with any appreciable improve- 
 jnent. To such let me say: You are accomplishing much more 
 than you think. You are fitting yourselves to appreciate and com- 
 prehend the discoveries of others: you are developing your pow- 
 ers of discernment, and your capacity to accept or criticize the 
 theories which may be based on new discoveries. Above all, 
 remember that, anomalous as it may seem, the failure to discover 
 is frequently as valuable as a discovery. 
 
 For example, had you selected for your field of observation 
 that region of the sky where the nova in Auriga has just been 
 discovered, even if you had not detected the stranger yourself, 
 you would have been able to render a valuable service to astronomy 
 by demonstrating that until a given night it was not visible, and 
 
thus have been the means of fixing accurately the date of its 
 apparition. 
 
 And again, how many have been the sharp discussions as to 
 changes in the lunar surface. Suppose that you had selected the 
 moon as your special field of observation, the fact that you had 
 observed no particular feature on a given region of the moon 
 when seen under all its varied angles of illumination, would be of 
 value in proving the disappearance of some crater or other object 
 which may have been delineated on lunar maps or described by 
 former observers. This kind of negative evidence is of high 
 value. 
 
 If you possess no optical appliances whatever, but have taken 
 an interest in photography, you can render an efficient service 
 to Astronomy by photographing as frequently as you are able 
 some particular region of the celestial sphere. An examination 
 of your plates from time to time may reward you with like dis- 
 coveries. Indeed, the photographic plate, when properly exposed, 
 has surpassed the greatest telescope in its revelations. Again, I 
 say, note accurately the time at which your plates are exposed, 
 and the length of exposure. Compare them frequently, and 
 record any apparent changes. 
 
 And here let me say that the climate of California is peculiarly 
 adapted to observational and photographic Astronomy. In the 
 great valleys the nights are almost uniformly clear from May 
 to November, and the winter and spring evenings, when not 
 clouded are exceptionally fine. I have no data as to the num- 
 ber of observing nights in those localities, but in San Irancisco 
 I have kept a record since October, 1888. Even in that place, 
 so much abused for its summer fogs and winter rains, there is a 
 considerable majority of the nights free from fogs and clouds. 
 Out of 1253 nights, I have a record of 1 182; of these, 645 were 
 unobscured by cloud or fog, and 537 obscured. Many of them 
 were first-class observing nights, in which the highest power of 
 the telescope could be used with advantage, and the remainder 
 of the 645 were more or less satisfactory with lower powers. 
 
 But you may have neither optical or photographic apparatus, 
 nor the opportunity or taste for observation. Then consider the 
 fertile field which yet remains in the department of theoretical 
 astronomy. I do not mean that we should indulge in mere con- 
 jecture or speculation. That is pernicious and idle to the last 
 degree. But the collation and examination and testing the ob- 
 
servations and data of others, and the working out of theories 
 and hypotheses is both instructive and interesting. 
 
 When we consider that the very foundation stones of planetary 
 astronomy, — the three immortal laws of Kepler, — were the re- 
 sults not of observation but of reasoning from the observations of 
 others, and that the "harmonic law" itself was but a long con- 
 tinued attempt at guessing the proportions between the periods 
 and distances of the planets; that the result when attained was 
 to him based on no principle, and, until the time of Newton, 
 wholly arbitrary, we may be encouraged to think that there are 
 other laws and other phenomena which might yield to the same 
 class of inquiry if earnestly pursued. 
 
 Take up one of the hundreds of unsolved problems and mys- 
 teries of the celestial universe. What is the Zodiacal light, the 
 Gegenschein, the Aurora Borealis, the solar corona, the substance 
 of comets? Why do the planets rotate on their axis; what is the 
 law governing that rotation ? Why are the orbits of the planets 
 inclined to the ecliptic if the nebular hypothesis be sound? Why 
 are the axis of the planets inclined to their orbits? W^hy do the 
 different portions of the Sun's and Jupiter' s surfaces rotate in dif- 
 ferent times? Why are there periods of maximum and minimum 
 sun spots? — and scores of other riddles which Nature, the Sphinx, 
 addresses to us. Mass your reading on the problem you take up. 
 Study all the observations at command. Frame your theories. 
 See how they meet all the facts. Do this, and I assure you that 
 you will find the pursuit as fascinating as it is instructive. If you 
 arrive at a conclusion which seems to you to amount to a working 
 hypothesis, communicate the result to the Society. Let it lead to 
 debate, discussion. Out of it will come your own improvement 
 in the science, and the instruction of us all. 
 
 A word of caution, and I have done. The enthusiasm of the 
 amateur is boundless. It is well that it is so. Do not conclude, 
 however, that the first dip into astronomy enables us to discuss 
 the complex problems of the sky with the veterans in science. 
 Be not too eager. Do not expect to discover a planet or a comet 
 the second night you observe, nor hope to expose a fallacy in the 
 law of gravitation on the first examination. Patience is genius. 
 As the master painter said when asked the secret of his art, 
 ** I mix my colors with my brains," so do you mix patience with 
 your observations, and conservatism with your reasoning. 
 
 In all your work, whether you have much or litde opportunity 
 
for it, remember that in science the future is richer than the past. 
 Valuable as have been the treasures extorted from reluctant Na- 
 ture, those yet to be rifled from her storehouse will far surpass 
 them. Be one of those who, like Sir John Herschel and his 
 two friends, recorded a vow to "do their best to leave the world 
 wiser than they found it." 
 
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