SEXUAL PERIODICITY IN MEN.
BY F. H. PERRY-COSTE, B. Sc. (LOND.).
In a recent brochure on the "Rhythm of the Pulse"[[373]] I showed inter alia that the readings of the pulse, in both man and woman, if arranged in lunar monthly periods, and averaged over several years, displayed a clear, and sometimes very strongly marked and symmetrical, rhythm.[[374]] After pointing out that, in at any rate some cases, the male and female pulse-curves, both monthly and annual, seemed to be converse to one another, I added: "It is difficult to ignore the suggestion that in this tracing of the monthly rhythm of the pulse we have a history of the monthly function in women; and that, if so, the tracing of the male pulse may eventually afford us some help in discovering a corresponding monthly period in men: the existence of which has been suggested by Mr. Havelock Ellis and Professor Stanley Hall, among other writers. Certainly the mere fact that we can trace a clear monthly rhythm in man's pulse seems to point strongly to the existence of a monthly physiological period in him also."
Obviously, however, it is only indirectly and by inference that we can argue from a monthly rhythm of the pulse in men to a male sexual periodicity; but I am now able to adduce more direct evidence that will fairly demonstrate the existence of a sexual periodicity in men.
We will start from the fact that celibacy is profoundly unnatural, and is, therefore, a physical—as well as an emotional and intellectual—abnormality. This being so, it is entirety in accord with all that we know of physiology that, when relief to the sexual secretory system by Nature's means is denied, and when, in consequence, a certain degree of tension or pressure has been attained, the system should relieve itself by a spontaneous discharge—such discharge being, of course, in the strict sense of the term, pathological, since it would never occur in any animal that followed the strict law of its physical being without any regard to other and higher laws of concern for its fellows.
Notoriously, that which we should have anticipated a priori actually occurs; for any unmarried man, who lives in strict chastity, periodically experiences, while sleeping, a loss of seminal fluid—such phenomena being popularly referred to as wet dreams.[[375]]
During some eight or ten years I have carefully recorded the occurrence of such discharges as I have experienced myself, and I have now accumulated sufficient data to justify an attempt to formulate some provisional conclusions.[[376]]
In order to render these observations as serviceable as may be to students of periodicity, I here repeat (at the request of Mr. Havelock Ellis) the statement which was subjoined, for the same reasons, to my "Rhythm of the Pulse." These observations upon myself were made between the ages of 20 and 33. I am about 5 feet, 9 inches tall, broad-shouldered, and weigh about 10 stone 3 lbs. net—this weight being, I believe, about 7 lbs. below the normal for my height. Also I have green-brown eyes, very dark-brown hair, and a complexion that leads strangers frequently to mistake me for a foreigner—this complexion being, perhaps, attributable to some Huguenot blood, although on the maternal side I am, so far as all information goes, pure English. I can stand a good deal of heat, enjoy relaxing climates, am at once upset by "bracing" sea-air, hate the cold, and sweat profusely after exercise. To this it will suffice to add that my temperament is of a decidedly nervous and emotional type.
Before proceeding to remark upon the various rhythms that I have discovered, I will tabulate the data on which my conclusions are founded. The numbers of discharges recorded in the years in question are as follows:—
| In 1886, | 30. | (Records commenced in April.) |
| In 1887, | 40. | |
| In 1888, | 37. | |
| In 1889, | 18. | (Pretty certainly not fully recorded.) |
| In 1890, | 0 | (No records kept this year.[[377]]) |
| In 1891, | 19. | (Records recommenced in June.) |
| In 1892, | 35. | |
| In 1893, | 40. | |
| In 1894, | 38. | |
| In 1895, | 36. | |
| In 1896, | 36. | |
| In 1897, | 35. | |
| Average, | 37. | (Omitting 1886, 1889, and 1891.) |
Thus I have complete records for eight years, and incomplete records for three more; and the remarkable concord between the respective annual numbers of observations in these eight years not only affords us intrinsic evidence of the accuracy of my records, but, also, at once proves that there is an undeniable regularity in the occurrence of these sexual discharges, and, therefore, gives us reason for expecting to find this regularity rhythmical. Moreover, since it seemed reasonable to expect that there might be more than one rhythm, I have examined my data with a view to discovering (1) an annual, (2) a lunar-monthly, and (3) a weekly rhythm, and I now proceed to show that all three such rhythms exist.
THE ANNUAL RHYTHM.
It is obvious that, in searching for an annual rhythm, we must ignore the records of the three incomplete years; but those of the remaining eight are graphically depicted upon [Chart VIII]. The curves speak so plainly for themselves that any comment were almost superfluous, and the concord between the various curves, although, of course, not perfect, is far greater than the scantiness of the data would have justified us in expecting. The curves all agree in pointing to the existence of three well-defined maxima,—viz., in March, June, and September,—these being, therefore, the months in which the sexual instinct is most active; and the later curves show that there is also often a fourth maximum in January. In the earlier years the March and June maxima are more strikingly marked than the September one; but the uppermost curve shows that on the average of all eight years the September maximum is the highest, the June and January maxima occupying the second place, and the March maximum being the least strongly marked of all.
Now, remembering that, in calculating the curves of the annual rhythm of the pulse, I had found it necessary to average two months' records together, in order to bring out the full significance of the rhythm, I thought it well to try the effect upon these curves also of similarly averaging two months together. At first my results were fairly satisfactory; but, as my data increased year by year, I found that these curves were contradicting one another, and therefore concluded that I had selected unnatural periods for my averaging. My first attempted remedy was to arrange the months in the pairs December-January, February-March, etc., instead of in January-February, March-April, etc.; but with these pairs I fared no better than with the former. I then arranged the months in the triplets, January-February-March, etc.; and the results are graphically recorded on [Chart VII]. Here, again, comment would be quite futile, but I need only point out that, on the whole, the sexual activity rises steadily during the first nine months in the year to its maximum in September, and then sinks rapidly and abruptly during the next three to its minimum in December.
The study of these curves suggests two interesting questions, to neither of which, however, do the data afford us an answer.
In the first place, are the alterations, in my case, of the maximum of the discharges from March and June in the earlier years to September in the later, and the interpolation of a new secondary maximum in January, correlated with the increase in age; or is the discrepancy due simply to a temporary irregularity that would have been equally averaged out had I recorded the discharges of 1881-89 instead of those from 1887 to 1897?
The second question is one of very great importance—socially, ethically, and physically. How often, in this climate, should a man have sexual connection with his wife in order to maintain himself in perfect physiological equilibrium? My results enable us to state definitely the minimum limits, and to reply that 37 embraces annually would be too few; but, unfortunately, they give us no clue to the maximum limit. It is obvious that the necessary frequency should be greater than 37 times annually,—possibly very considerably in excess thereof,—seeing that the spontaneous discharges, with which we are dealing, are due to over-pressure, and occur only when the system, being denied natural relief, can no longer retain its secretions; and, therefore, it seems very reasonable to suggest that the frequency of natural relief should be some multiple of 37. I do not perceive, however, that the data in hand afford us any clue to this multiple, or enable us to suggest either 2, 3, 4, or 5 as the required multiple of 37. It is true that other observations upon myself have afforded me what I believe to be a fairly satisfactory and reliable answer so far as concerns myself; but these observations are of such a nature that they cannot be discussed here, and I have no inclination to offer as a counsel to others an opinion which I am unable to justify by the citation of facts and statistics. Moreover, I am quite unable to opine whether, given 37 as the annual frequency of spontaneous discharges in a number of men, the multiple required for the frequency of natural relief should be the same in every case. For aught I know to the contrary, the physiological idiosyncrasies of men may be so varied that, given two men with an annual frequency of 37 spontaneous discharges, the desired multiple may be in one case X and in the other 2X.[[378]] Our data, however, do clearly denote that the frequency in the six or eight summer months should bear to the frequency of the six or four winter months the proportion of three or four to two.[[379]] It should never be forgotten, however, that, under all conditions, both man and wife should exercise prudence, both selfward and otherward, and that each should utterly refuse to gratify self by accepting a sacrifice, however willingly offered, that may be gravely prejudicial to the health of the other; for only experience can show whether, in any union, the receptivity of the woman be greater or less than, or equal to, the physical desire of the man. To those, of course, who regard marriage from the old-fashioned and grossly immoral standpoint of Melancthon and other theologians, and who consider a wife as the divinely ordained vehicle for the chartered intemperance of her husband, it will seem grotesque in the highest degree that a physiological inquirer should attempt to advise them how often to seek the embraces of their wives; but those who regard woman from the standpoint of a higher ethics, who abhor the notion that she should be only the vehicle for her husband's passions, and who demand that she shall be mistress of her own body, will not be ungrateful for any guidance that physiology can afford them. It will be seen presently, moreover, that the study of the weekly rhythm does afford us some less inexact clue to the desired solution.
One curious fact may be mentioned before we quit this interesting question. It is stated that "Solon required [of the husband] three payments per month. By the Misna a daily debt was imposed upon an idle vigorous young husband; twice a week on a citizen; once in thirty days on a camel-driver; once in six months on a seaman."[[380]] Now it is certainly striking that Solon's "three payments per month" exactly correspond with my records of 37 discharges annually. Had Solon similarly recorded a series of observations upon himself?
THE LUNAR-MONTHLY RHYTHM.
We now come to that division of the inquiry which is of the greatest physiological interest, although of little social import. Is there a monthly period in man as well as in woman? My records indicate clearly that there is.
In searching for this monthly rhythm I have utilized not only the data of the eight completely-recorded years, but also those of the three years of 1886, 1889, and 1891, for, although it would obviously have been inaccurate to utilize these incomplete records when calculating the yearly rhythm, there seems no objection to making use of them in the present section of the inquiry. It is hardly necessary to remark that the terms "first day of the month," "second day," "third day," etc., are to be understood as denoting "new-moon day," "day after new moon," "third lunar day," and so on; but it should be explained that, since these discharges occur at night, I have adopted the astronomical, instead of the civil, day; so that a new moon occurring between noon yesterday and noon to-day is reckoned as occurring yesterday, and yesterday is regarded as the first lunar day: thus, a discharge occurring in the night between December 31st and January 1st is tabulated as occurring on December 31st, and, in the present discussion, is assigned to the lunar day comprised between noon of December 31st and noon of January 1st.
Since it is obvious that the number of discharges in any one year—averaging, as they do, only 1.25 per day—are far too few to yield a curve of any value, I have combined my data in two series. The dotted curve on [Chart IX] is obtained by combining the results of the years 1886-92: two of these years are incompletely recorded, and there are no records for 1890; the total number of observations was 179. The broken curve is obtained by combining those of the years 1893-97, the total number of observations being 185. Even so, the data are far too scanty to yield a really characteristic curve; but the continuous curve, which sums up the results of the eleven years, is more reliable, and obviously more satisfactory.
If the two former curves be compared, it will be seen that, on the whole, they display a general concordance, such differences as exist being attributable chiefly to two facts: (1) that the second curve is more even throughout, neither maximum nor minimum being so strongly marked as in the first; and (2) that the main maximum occurs in the middle of the month instead of on the second lunar day, and the absence of the marked initial maximum alters the character of the first week or so of this curve. It is, however, scarcely fair to lay any great stress on the characters of curves obtained from such scanty data, and we will, therefore, pass to the continuous curve, the study of which will prove more valuable.[[381]]
Now, even a cursory examination of this continuous curve will yield the following results:—
1. The discharges occur most frequently on the second lunar day.
2. The days of the next most frequent discharges are the 22d; the 13th; the 7th, 20th, and 26th; the 11th and 16th; so that, if we regard only the first six of these, we find that the discharges occur most frequently on the 2d, 7th, 13th, 20th, 22d, and 26th lunar days—i.e., the discharges occur most frequently on days separated, on the average, by four-day intervals; but actually the period between the 20th and 22d days is that characterized by the most frequent discharges.
3. The days of minimum of discharge are the 1st, 5th, 15th, 18th, and 21st.
4. The curve is characterized by a continual see-sawing; so that every notable maximum is immediately followed by a notable minimum. Thus, the curve is of an entirely different character from that representing the monthly rhythm of the pulse,[[382]] and this is only what one might have expected; for, whereas the mean pulsations vary only very slightly from day to day,—thus giving rise to a gradually rising or sinking curve,—a discharge from the sexual system relieves the tension by exhausting the stored-up secretion, and is necessarily followed by some days of rest and inactivity. In the very nature of the case, therefore, a curve of this kind could not possibly be otherwise than most irregular if the discharges tended to occur most frequently upon definite days of the month; and thus the very irregularity of the curve affords us proof that there is a regular male periodicity, such that on certain days of the month there is greater probability of a spontaneous discharge than on any other days.
5. Gratifying, however, though this irregularity of the curve may be, yet it entails a corresponding disadvantage, for we are precluded thereby from readily perceiving the characteristics of the monthly rhythm as a whole. I thought that perhaps this aspect of the rhythm might be rendered plainer if I calculated the data into two-day averages; and the result, as shown in [Chart X], is extremely satisfactory. Here we can at once perceive the wonderful and almost geometric symmetry of the monthly rhythm; indeed, if the third maximum were one unit higher, if the first minimum were one unit lower, and if the lines joining the second minimum and third maximum, and the fourth maximum and fourth minimum, were straight instead of being slightly broken, then the curve would, in its chief features, be geometrically symmetrical; and this symmetry appears to me to afford a convincing proof of the representative accuracy of the curve. We see that the month is divided into five periods; that the maxima occur on the following pairs of days: the 19th-20th, 13th-14th, 25th-26th, 1st-2d, 7th-8th; and that the minima occur at the beginning, end, and exact middle of the month. There have been many idle superstitions as to the influence of the moon upon the earth and its inhabitants, and some beliefs that—once deemed equally idle—have now been re-instated in the regard of science; but it would certainly seem to be a very fascinating and very curious fact if the influence of the moon upon men should be such as to regulate the spontaneous discharges of their sexual system. Certainly the lovers of all ages would then have "builded better than they knew," when they reared altars of devotional verse to that chaste goddess Artemis.
THE WEEKLY RHYTHM.
We now come to the third branch of our inquiry, and have to ask whether there be any weekly rhythm of the sexual activity. A priori it might be answered that to expect any such weekly rhythm were absurd, seeing that our week—unlike the lunar month of the year—is a purely artificial and conventional period; while, on the other hand, it might be retorted that the existence of an induced weekly periodicity is quite conceivable, such periodicity being induced by the habitual difference between our occupation, or mode of life, on one or two days of the week and that on the remaining days. In such an inquiry, however, a priori argument is futile, as the question can be answered only by an induction from observations, and the curves on Chart XI ([Chart XIa] and [Chart XIb]) prove conclusively that there is a notable weekly rhythm. The existence of this weekly rhythm being granted, it would naturally be assumed that either the maximum or the minimum would regularly occur on Saturday or Sunday; but an examination of the curves discloses the unexpected result that the day of maximum discharge varies from year to year. Thus it is[[383]]
| Sunday in | 1888, 1892, 1896. |
| Tuesday in | 1894. |
| Thursday in | 1886, 1897. |
| Friday in | 1887. |
| Saturday in | 1893 and 1895. |
Since, in Chart XI, the curves are drawn from Sunday to Sunday, it is obvious that the real symmetry of the curve is brought out in those years only which are characterized by a Sunday maximum; and, accordingly, in Chart 12 I have depicted the curves in a more suitable form.
[Chart XII] A is obtained by combining the data of 1888, 1892, and 1896: the years of a Sunday maximum. Curve 12 B represents the results of 1894, the year of a Tuesday maximum—multiplied throughout by three in order to render the curve strictly comparable with the former. Curve 12 C represents 1886 and 1897—the years of a Thursday maximum—similarly multiplied by 1.5. In Curve 12 D we have the results of 1887—the year of a Friday maximum—again multiplied by three; and in Curve 12 E those of 1893 and 1895—the years of a Saturday maximum—multiplied by 1.5. Finally, Curve 12 F represents the combined results of all nine years plus (the latter half of) 1891; and this curve shows that, on the whole period, there is a very strongly marked Sunday maximum.
I hardly think that these curves call for much comment. In their general character they display a notable concord among themselves; and it is significant that the most regular of the five curves are A and E, representing the combinations of three years and of two years, respectively, while the least regular is B, which is based upon the records of one year only. In every case we find that the maximum which opens the week is rapidly succeeded by a minimum, which is itself succeeded by a secondary maximum,—usually very secondary, although in 1894 it nearly equals the primary maximum,—followed again by a second minimum—usually nearly identical with the first minimum,—after which there is a rapid rise to the original maximum. The study of these curves fortunately amplifies the conclusion drawn from our study of the annual rhythm, and suggests that, in at least part of the year, the physiological condition of man requires sexual union at least twice a week.
As to Curve 12F, its remarkable symmetry speaks for itself. The existence of two secondary maxima, however, has not the same significance as had that of our secondary maximum in the preceding curves; for one of these secondary maxima is due to the influence of the 1894 curve with its primary Tuesday maximum, and the other to the similar influence of Curve C with its primary Thursday maximum. Similarly, the veiled third secondary maximum is due to the influence of Curve E. Probably, any student of curves will concede that, on a still larger average, the two secondary maxima of Curve F would be replaced by a single one on Wednesday or Thursday.
One more question remains for consideration in connection with this weekly rhythm. Is it possible to trace any connection between the weekly and yearly rhythms of such a character that the weekly day of maximum discharge should vary from month to month in the year; in other words, does the greater frequency of a Sunday discharge characterize one part of the year, that of a Tuesday another, and so on? In order to answer this question I have re-calculated all my data, with results that are graphically represented in [Chart XIII]. These curves prove that the Sunday maxima discharges occur in March and September, and the minima in June; that the Monday maxima discharges occur in September, Friday in July, and so on. Thus, there is a regular rhythm, according to which the days of maximum discharge vary from one month of the year to another; and the existence of this final rhythm appears to me very remarkable. I would especially direct attention to the almost geometric symmetry of the Sunday curve, and to the only less complete symmetry of the Thursday and Friday curves. Certainly in these rhythms we have an ample field for farther study and speculation.
I have now concluded my study of this fascinating inquiry; a study that is necessarily incomplete, since it is based upon records furnished by one individual only. The fact, however, that, even with so few observations, and notwithstanding the consequently exaggerated disturbing influence of minor irregularities, such remarkable and unexpected symmetry is evidenced by these curves, only increases one's desire to have the opportunity of handling a series of observations sufficiently numerous to render the generalizations induced from them absolutely conclusive. I would again appeal[[384]] to heads of colleges to assist this inquiry by enlisting in its aid a band of students. If only one hundred students, living under similar conditions, could be induced to keep such records with scrupulous regularity for only twelve months, the results induced from such a series of observations would be more than ten times as valuable as those which have only been reached after ten years' observations on my part; and, if other centuries of students in foreign and colonial colleges—e.g., in Italy, India, Australia, and America—could be similarly enlisted in this work, we should quickly obtain a series of results exhibiting the sexual needs and sexual peculiarities of the male human animal in various climates. Obviously, however, the records of any such students would be worse than useless unless their care and accuracy, on the one hand, and their habitual chastity, on the other, could be implicitly guaranteed.
First published in the University Magazine and Free Review of February, 1898, and since reprinted as a pamphlet. A preliminary communication appeared in Nature, May 14, 1891.
[Later study (1906) has convinced me that my attempt to find a lunar-monthly period in the female pulse was vitiated by a hopeless error: for any monthly rhythm in a woman must be sought by arranging her records according to her own menstrual month; and this menstrual month may vary in different women, from considerably less than a lunar month to thirty days or more.]
I may add, however, that in my own case these discharges are—so far as I can trust my waking consciousness—frequently, if not usually, dreamless; and that strictly sexual dreams are extremely rare, notwithstanding the possession of a strongly emotional temperament.
If I can trust my memory, I first experienced this discharge when a few months under fifteen years of age, and, if so, within a few weeks of the time when I was, in an instant, suddenly struck with the thought that possibly the religion in which I had been educated might be false. It is curiously interesting that the advent of puberty should have been heralded by this intellectual crisis.
This unfortunate breach in the records was due to the fact that, failing to discover any regularity in, or law of, the occurrences of the discharges, I became discouraged and abandoned my records. In June, 1891, a re-examination of my pulse-records having led to my discovery of a lunar-monthly rhythm of the pulse, my interest in other physiological periodicities was reawakened, and I recommenced my records of these discharges.
As a matter of fact, I take it that we may safely assert that no man who is content to be guided by his own instinctive cravings, and who neither suppresses these, on the one hand, nor endeavors to force himself, on the other hand, will be in any danger of erring by either excess or the contrary.
[It is obvious that the opportunity of continuing such an inquiry as that described in this Appendix, ceases with marriage; but I may add (1906) that certain notes that I have kept with scrupulous exactness during eight years of married life, lend almost no support to the suggestion made in the text—i.e., that sexual desire is greater at one season of the year than at another. The nature of these notes I cannot discuss; but, they clearly indicate that, although there is a slight degree more of sexual desire in the second and third quarters of the year, than in the first and fourth, yet, this difference is so slight as to be almost negligible. Even if the months be rearranged in the triplets—November-December-January, etc.,—so as to bring the maximum months of May, June, and July together, the difference between the highest quarter and the lowest amounts to an increase of only ten per cent, upon the latter—after allowing, of course, for the abnormal shortness of February; and, neglecting February, the increase in the maximum months (June and July) over the minimum (November) is equal to an increase of under 14 per cent, upon the latter. These differences are so vastly less than those shown on [Chart VII] that they possess almost no significance: but, lest too much stress be laid upon the apparently equalizing influence of married life, it must be added that the records discussed in the text were obtained during residence in London, whereas, since my marriage, I have lived in South Cornwall, where the climate is both milder and more equable.]
Selden's Uxor Hebraica as quoted in Gibbon's Decline and Fall, vol. v, p. 52, of Bonn's edition.
I may add that the curve yielded by 1896-97 is remarkably parallel with that yielded by the preceding nine years, but I have not thought it worth while to chart these two additional curves.
See "Rhythm of the Pulse," [Chart IV].
As will be observed, I have omitted the results of the incompletely recorded years of 1889 and 1891. The apparent explanation of this curious oscillation will be given directly.
See "Rhythm of the Pulse," p. 21.