Jan. Feb. Mar. Apr. May June July Aug. Sept. Oct. Nov. Dec.
10.511.4118.310.210.511.512.612.311.61211.7

There is thus a well-marked minimum of conceptions (a depression appearing here in each of the three periods, separately) about the month of July. (In the second period, however, which contains the smallest number of births, the minimum occurs in September.) From that low minimum there is steady and unbroken rise up to the chief maximum in November. (In the first period, however, the maximum is delayed till January, and in the second period it is somewhat diffused.) There is a tendency to a minor maximum in February, specially well marked in the third and most important period, and in the first period delayed until March.

A very curious and perhaps not accidental coincidence might be briefly pointed out before we leave this part of the subject. It is found[[157]] by taking 3000 cases of children dying under one year that, among the general population, children born in February and September (and therefore conceived in May and December) appear to possess the greatest vitality, and those born in June, and, therefore, conceived in September, the least vitality.[[158]] As we have seen, May and December are precisely the periods when conceptions in Europe generally are at a maximum, and September is precisely the period when they are at a minimum, so that, if this coincidence is not accidental, the strongest children are conceived when there is the strongest tendency to procreate, and the feeblest children when that tendency is feeblest.

Nelson, in his study of dreams and their relation to seasonal ecbolic manifestations, does not present any yearly ecbolic curve, as the two years and a half over which his observations extend scarcely supply a sufficient basis. On examining his figures, however, I find there is a certain amount of evidence of a yearly rhythm. There are spring and autumn climaxes throughout (in February and in November); there is no December rise. During one year there is a marked minimum from May to September, though it is but slightly traceable in the succeeding year. These figures are too uncertain to prove anything, but, as far as they go, they are in fair agreement with the much more extensive record, that of W. K. (ante p. 113), which I have already made use of in discussing the question of a monthly rhythm. This record, covering nearly twelve years, shows a general tendency, when the year is divided into four periods (November-January, February-April, May-July, August-October) and the results summated, to rise steadily throughout, from the minimum in the winter period to the maximum in the autumn period. This steady upward progress is not seen in each year taken separately. In three years there is a fall in passing from the November-January to the February-April quarter (always followed by a rise in the subsequent quarter); in three cases there is a fall in passing from the second to the third quarter (again always followed by a rise in the following quarter), and in two successive years there is a fall in passing from the third to the fourth quarter. If, however, beginning at the second year, we summate the results for each year with those for all previous years, a steady rise from season to season is seen throughout. If we analyze the data according to the months of the year, still more precise and interesting results (as shown in the curve, [Chart III]) are obtained; two maximum points are seen, one in spring (March), one in autumn (October, or, rather, August-October), and each of these maximum points is followed by; a steep and sudden descent to the minimum points in April and in December. If we compare this result with Perry-Coste's also extending over a long series of years, we find a marked similarity. In both alike there are spring and autumn maxima, in both the autumn maximum is the highest, and in both also there is an intervening fall. In both cases, again, the maxima are followed by steep descents, but while in both the spring maximum occurs in March, in Perry-Coste's case the second maximum, though of precisely similar shape, occurs earlier, in June-September instead of August-October. In Perry-Coste's case, also, there is an apparently abnormal tendency, only shown in the more recent years of the record, to an additional maximum in January. The records certainly show far more points of agreement than of discrepancy, and by their harmony, as well with each other as with themselves, when the years are taken separately, certainly go far to prove that there is a very marked annual rhythm in the phenomena of seminal emissions during sleep, or, as Nelson has termed it, the ecbolic curve. We see, also, that the great yearly organic climax of sexual effervescence corresponds with the period following harvest, which, throughout the primitive world, has been a season of sexual erethism and orgy; though those customs have died out of our waking lives, they are still imprinted on our nervous texture, and become manifest during sleep.

The fresh records that have reached me since the first edition of this book was published show well-marked annual curves, though each curve always has some slight personal peculiarities of its own. The most interesting and significant is that of E. M. (see ante p. 116), covering four years. It is indicated by the following monthly frequencies, summated for the four years:—

Jan. Feb. Mar. Apr. May June July Aug. Sept. Oct. Nov. Dec.
16 13 14 22 19 19 12 12 14 14 12 24

E. M. lives in India. April, May, and June, are hot months, but not unhealthy, and during this season, moreover, he lives in the hills, under favorable conditions, getting plenty of outdoor exercise. July, August, and September, are nearly as hot, but much damper, and more trying; during these months, E. M. is living in the city, and his work is then, also, more exacting than at other times, September is the worst month of all; he has a short holiday at the end of it. During December, January, and February, the climate is very fine, and E. M.'s work is easier. It will be seen that his ecbolic curve corresponds to his circumstances and environment, although until he analyzed the record he had no idea that any such relationship existed. Unfavorable climatic conditions and hard work, favorable conditions and lighter work, happen to coincide in his life, and the former depress the frequency of seminal emissions; the latter increase their frequency. At the same time, the curve is not out of harmony with the northern curves. There is what corresponds to a late spring (April) climax, and another still higher, late autumn (December) climax. A very interesting point is the general resemblance of the ecbolic curves to the Indian conception-curves as set forth by Hill (ante p. 140). The conception-curve is at its lowest point in September, and at its highest point in December-January, and this ecbolic curve follows it, except that both the minimum and the maximum are reached a little earlier. When compared with the English annual ecbolic curves (W. K. and Perry-Coste), both spring and autumn maxima fall rather later, but all agree in representing the autumn rise as the chief climax.

The annual curve of A. N. (ante p. 117), who lives in Indiana, U.S.A., also covers four years. It presents the usual spring (May-June, in this case) and autumn (September-October) climaxes. The exact monthly results, summated for the four years, are given below; in order to allow for the irregular lengths of the months, I have reduced them to daily averages, for convenience treating the four years as one year:—

Jan. Feb. Mar. Apr. May June July Aug. Sept. Oct. Nov. Dec.
13 9 13 20 23 22 20 20 21 23 9 16
.42 .32 .42 .66 .74 .73 .64 .64 .70 .74 .30 .52

In his book on Adolescence, Stanley Hall refers to three ecbolic records in his possession, all made by men who were doctors of philosophy, and all considering themselves normal. The best of these records made by "a virtuous, active and able man," covered nearly eight years. Stanley Hall thus summarizes the records, which are not presented in detail: "The best of these records averages about three and a half such experiences per month, the most frequent being 5.14 for July, and the least frequent 2.28, for September, for all the years taken together. There appears also a slight rise in April, and another in November, with a fall in December." The frequency varies in the different individuals. There was no tendency to a monthly cycle. In the best case, the minimum number for the year was thirty-seven, and the maximum, fifty. Fifty-nine per cent. of all were at an interval of a week or less; forty per cent. at an interval of from one to four days; thirty-four per cent, at an interval of from eight to seventeen days, the longest being forty-two days. Poor condition, overwork, and undersleep, led to infrequency. Early morning was the most common time. Normally there was a sense of distinct relief, but in low conditions, or with over-frequency, depression. (G. S. Hall, Adolescence, vol. i, p. 453.) I may add that an anonymous article on "Nocturnal Emissions" (American Journal of Psychology, Jan., 1904) is evidently a fuller presentation of the first of Stanley Hall's three cases. It is the history of a healthy, unmarried, chaste man, who kept a record of his nocturnal emissions (and their accompanying dreams) from the age of thirty to thirty-eight. In what American State he lived is not mentioned. He was ignorant of the existence of any previous records. The yearly average was 37 to 50, remaining fairly constant; the monthly average was 3.43. I reproduce the total results summated for the months, separately, and I have worked out the daily average for each month, for convenience counting the summated eight years as one year:—