October 25, 1927

Mr. F. A. Linn
101 West 31st Street
New York City

Dear Sirs,

I am interested in your letter of October 24th.
At present however, I do not see any way in which I could
use your list. I will put your letter away for reference
and if I see any way in which your information could be
used, I will communicate with you.

I fully appreciate the fact that your informa-
tion is confidential. Would you wish me to speak of it
to Mrs. Margaret Sanger of the American Birth Control
League or to Mr. Leon F. Whitney, Secretary of the Ameri-
can Eugenics Society?

Yours very truly

EH: h

Copy sent L.F.W.

Mr. F. R. Barnes
Internal Revenue Service
Grand Forks, N.D.

April 30, 1926

Dear Sir;

Your letter addressed to Professor Huntington at 185 Church Street, New Haven, has been received in this office. I am forwarding it to Mr. Leon F. Whitney, 185 Church Street, Secretary of the American Eugenics Society who can no doubt send you the literature you ask for. Mr. Whitney was associated with Professor Huntington last year in writing The Builders of America, which deals in a broad way with eugenics.

Copy for American Eugenics Society

May 11th, 1926

Miss Vida H. Peene
217 Mountain View Apartments
Hamilton, Ontario

Dear Madam;

I have read Mr. Wiggam's book *The Next Age of Man*, but did not realize that he advised his readers to write me for a pamphlet entitled *A Catechism of Eugenics*. Perhaps this is added in a later edition. The Catechism is published by the American Eugenics Society, and I am asking them to send you a copy. I am not the author however, but was merely one of many who made certain suggestions. My own work on eugenics is contained in a book called *The Builders of America*, published by Wm. Morrow & Co. Inc., 386 Fourth Avenue, New York City.

The price is $3.50. I think that the book will probably interest you.

EH:h

INTRODUCTION

The following outline is intended to be merely
tentative and suggestive. Suggestions for its improvement
will be welcomed from all sources. Numerous of the items
could be expanded into almost unlimited detail. In time,
it may be desirable for specialists in various branches to
undertake such amplification. The research in these spe-
cialized fields, assumed in this outline, is obviously
only that which has a bearing on problems of population.

A population, as understood in this outline, is
a group of men, women, and children coordinated into that
type of community ordinarily designated as a "society."
The concept of population has a range corresponding to that
of the concept of society. It may run from relatively
small units at one extreme to the total of humanity at
the other extreme.

The outline concerns itself exclusively with re-
search. Even in the applied branches, the subject matter
is research into purposes and methods of application. This
outline has nothing to do with the actual, active achieve-
ment of results.

The words "eugenics" and "euthenics" are intrin-
sically not well chosen, since the use of the prefix "eu"
implies a value judgment, which should be entirely lacking
in the field of theoretic research, and even in the applied
field should not be presupposed or taken for granted. How-
ever, the former is well established, and the latter is
consistent with it, and it would be apart from the purpose
of this outline to advocate changes.

Section I. A. 1. B. 3. b. (cont.)

Occupation

Affecting fertility or fecundity

Of men

Of women

Home

Type of domicile

Rooms, number, arrangement, uses, etc.

Sleeping arrangements

Broadwinners

Recreation

In the home

Out of the home

Theatres

Movies

Dance halls

Recreation centers

Parks

Automobiles

Road-houses

Etc., etc.

Moral code

Double standard

Chaperonage

Modesty

Petting

Type of community

Rural

Small town

City

Artificial control

Social - enforced

Sterilization

Segregation

Personal - volitional. Birth Control.

Abstinence

Contraception

Abortion

c. Sex habits

Pre-marital

Chastity

Indulgence

Heterosexual

Promiscuity

Varied illicit relationships

Homosexual

Autoerotic

Marital

Frequency of intercourse

Habits of intercourse

Modes

Preliminaries

Time of day

Etc., etc.

Double or single beds

Separate rooms

-2-

How many more children will be born to these eugenists?
Little is to be expected from the 18% of childless marriages
in the above tabulation, for the mean age of the childless
is 50.50 1.68 years (none of them being under 40 and four-
fifths being over 50), and the mean duration of their
marriages is 29.85 1.76 years, only one being less than
15 years.

The mean age in 1927 of the whole group of eugenists
is 55.87 .65. Their mean age at marriage was 30.15 .52.
Of the fertile marriages there are only 21 of which the
duration is now less than 20 years. Any further increase
in the number of children produced by this group must
therefore, in all probability, come from some of these 21
marriages.

The crude correlation ratio between duration of
marriage and number of living children, N=.09, in view of
the necessary correction and the probable error, is
simply 0. There is thus no constant relation whatever
between the length of time a man has been married, and
the size of his family, in this group. While the figures
are only approximate, owing to uncertainty as to whether
the wife is living or dead, I believe the conclusion is
substantially valid.

Making all possible allowance for future increase,
it is inconceivable that the prominent American eugenists,
as a whole, form a self-perpetuating group. Only one in
five now has enough children for that purpose.

It is a nice question to what extent some of
these people are eugenists in spite of, and to what
extent they are eugenists because of, their childlessness.
In many instances, no doubt, undesired sterility or nec-
essary limitation of offspring has made the individual
keenly aware of his deprivation and a compensatory mental
mechanism is at work.

But the purpose of the present note is merely
to put on record a few interesting facts, not to interpret
them.

*****

BIBLIOGRAPHY

American Family Statistics

Baber, Ray Erwin and
Ross, Edward Alsworth

Changes in the size of American families in one generation.
University of Wisconsin Studies in the Social Sciences and History, Number 10, 1924, 99 pp.

Bailey, W. B.

Size of American families.
Independent, 1911, Number 71, p.134.

Bureau of the Census - Department of Commerce

Birth, stillbirth and infant mortality statistics for the
birth registration area of the United States: 1923 :
Ninth Annual Report - 1925.
(See Table 10, p. 171)

Birth statistics for the birth registration area of the
United States : 1920 :
Sixth Annual Report - 1922 : 257 pp. (See especially
table p.18)

Size of families of women aged 35 to 44 who became mothers
in 1924, by occupations of husbands.
Mimeographed report of four pages, 1926.

Cattell, J. McKeen

Families of American men of science.
II - Marriages and number of children.
The Scientific Monthly, March, 1917 : p.243.

Davis, W. H.

Size families in relation to nationality, occupation and
economic condition.
Trans. American Association for the Study and Prevention
of Infant Mortality - 3 - p. 119, 1913.

Douglas, Paul

Is family of five typical?
J. A. S. Association, September : 1924.

- 2 -

Dunlop, James Crauford

The fertility of marriage in Scotland : a Census Study.
Journal Royal Statistical Society : February, 1914 : p. 259

A further note on the fertility of marriage in Scotland.
Journal Royal Statistical Society : January, 1915 : p. 35.

Fertility of marriage

Census of England and Wales, 1911, Vol. XIII, Part II,
1923 : 260 pp.

Green, C. V. and
Hunt, H. R.

Birthrates in the families of Michigan State College Graduates.
Journal of Heredity, October, 1925, p. 361.

Greenwood, Brown and Wood

Fertility of English middle classes.
Eugenics Review, Number 12, p.158.

Hall and Smith

Marriage and fecundity of college men and women.
Pedagog. Sem. Number 10: 1903; p. 275.

Hart, Hornell

Differential fecundity in Iowa: University of Iowa Studies in Child Welfare.
Volume II, Number II, June, 1922.

The Harvard Birth Rate

Journal of Heredity, March, 1926 : p.109.

Hill, Joseph A. (Assisted by Julius H. Parmelee)

Comparative fecundity of women of native and foreign parentage
in the United States.
Journal American Statistical Association, December, 1913 : p. 583.

Marriage Statistics in United States.
International Congress on Hygiene and Demography, Volume 6,
1913 : p. 202.

Holmes, Samuel J.

The trend of the race.
Harcourt Brace & Company, 1921 : 396

- 3 -

Holmes, Samuel J.

The size of college families.

Journal of Heredity, October, 1924 : p.407.

A bibliography of eugenics.

University of California Press : 1924 p.514.

Birth rate references - p.288 - 340.

Hunt, H. R.

The Allegany College birth rate.

Journal of Heredity, May, 1923 : p.51.

Johnson, Roswell and

Stutzmann, Bertha

Wellesley's birth rate.

Journal of Heredity, June, 1915 : Volume VI, Number 6, p.250.

Kopf, Edwin W.

Essentials of family statistics.

Proceedings Casualty Actuarial Society of America, Volume V,

Part I, Number 11, 1918.

Lenz, Fritz

Are the gifted families in America maintaining themselves?

Eugenics News, January, 1926 : p.2.

Nearing, Nellie S.

Education and fecundity.

J. A. S. Association, June, 1914.

(American Statistical)

Newcomer, Mabel

Vital statistics from Vassar College.

A. J. Sociology, 1924 : p.430.

(American Journal of Sociology)

Nicolson, Frank W.

Family records of graduates of Wesleyan University.

Science, N. S. Number 36, 1912 : p.74.

Phillips, J. C.

A study of the birth rate in Harvard and Yale graduates.

Harvard Graduates Magazine, September : 1916 :

- 4 -

Popenoe, Paul and
Johnson, Roswell Hill

Applied eugenics.
Macmillan Company : New York : 1918, P.459 pp.

Rice, S. A. and
Willey, M. M.

College men and the birth rate.
Journal of Heredity, January; 1926, Page 11.

Stevenson, T. H. C.

Fertility of various social classes, England and Wales.
Journal Royal Statistical Society : May, 1920 : p.401.

Thompson, Warren S.

Size of families from which college students come.
Journal American Statistical Association, December, 1925 : p.431.

Natural Increase of Population.
Population Problems in the United States and Canada - Edited
by Louis I. Dublin : Houghton Mifflin Company : 1926 : p.33.

Thorndike, Edward

Decrease in size of American families.
Popular Science Monthly, Volume 63: 1903 : p.64.

Van Kleek, Mary

A census of college women.
Journal of Association of Collegiate Alumnae, May, 1918.

Willcox, Walter F.

Differential fecundity.
Journal of Heredity, Volume 5: 1914 : p.141.

Savorgnan, F.

La Fecondita delle Aristocrazie, Metron Page 558

Frederick C. Crum

Decadence of Native American Stock

H.H.Hibbs

Infant Mortality and the Size of Family:
Journal American Statistical Association -1914-15 Vol. 14, page 629

Dublin & Langman

The Handicapping of the First Born
Journal of the American Statistical Association, 1914, Vol.14, page 727

Human Blood Groups: thier Inheritance and Racial Significance.

Laurence H. Snyder
Genetics Laboratory, N. C. State College.

(Abstract)

A study of two hundred human families is given, showing that the four blood groups are inherited as a series of three multiple allelomorphs, and not as two independent pairs of factors, as has long been supposed. On this basis, the frequency of each of the three factors in any race can be computed. These frequencies (p, q and r) are used as the basis of a classification of races, Races classified on this basis show remarkable geographic relationships.

The group frequencies are given for American Indians, Dutch, Maltans, American negroes, and several types of neuropathic conditions among whites (epilepsy, dementia praecox, feeble-mindedness). A graded series is made with pure-blood Indians, mixed Indians and whites, showing in a striking manner the effects of crossing on the proportions of the groups.

[Reprinted from the Journal of the AMERICAN STATISTICAL ASSOCIATION, September, 1926.]

THE SIZE OF FAMILIES
A DISCUSSION OF SAMPLING

BY ELBRIDGE SIBLEY

Professor Pietra sets forth a point of methodology which the writer had raised less nicely at about the same time. It seems to be possible to carry the same line of reasoning further, to apply to the problem of computing not only the average size of parents' families from a sample of the filial generation, but also the average size of grandparents' families. The latter problem is involved in such studies as the recent one of Professor Thompson¹ cited by Professor Pietra, and that of Baber and Ross,² both of which show astonishing differences in the average sizes of families in the two generations.

It may be stated in general that the probability of a given person's being represented by one descendant in a random sample of a later generation is in exact proportion to the number of descendants that that person has in the generation from which the sample is drawn. It is further apparent that the number of descendants that a person has will equal the number of his children, multiplied by the average number of (grand-) children born to each of them, and so on.

We shall consider in detail only the case of grandparents and grandchildren, although the method would be applicable to any number of generations.

If in a given population there are $f_n$ families having $n$ children each, and the $nf_n$ persons in the second generation have an average of $p_n$ children apiece (it being assumed that there is no intermarriage), the third generation will number $nf_n p_n$. Now if we denote the number of individuals in the third generation by $q_n$,

$$q_n = nf_n p_n \qquad (1)$$

whence

$$f_n = q_n / n p_n. \qquad (2)$$

The average size of the first generation families,

$$\bar{N} = \frac{\sum n f_n}{\sum f_n} \qquad (3)$$

¹ This JOURNAL, December, 1925.

² University of Wisconsin Studies in Social Science, No. 10, 1924.

334

[78]

Substituting the value of $f_n$ from equation (2) gives

$$ \bar{N} = \frac{\sum n(q_n/np_n)}{\sum(q_n/np_n)} = \frac{\sum(q_n/p_n)}{\sum(q_n/np_n)}. \quad (4) $$

The mean sizes of grandparental families given in the studies cited have evidently been computed without regard to the weighting of the sample, from the equation

$$ \bar{N} = \frac{\sum nq_n}{\sum q_n}. \quad (5) $$

From equations (4) and (5) it is seen that the relationship between the true mean size of the grandparents' families ($\bar{N}$) and the computed value ($\bar{N}_1$) depends upon (a) the relation between $n$ and $f_n$, and (b) the relation between $n$ and $p_n$. Professor Pietra takes account of the first factor by using the formula

$$ \bar{N}_2 = \frac{\sum q_n}{\sum (q_n/n)} \quad (6) $$

and he points out that (unless all the families in the population be of the same size)

$$ \bar{N}_1 > \bar{N}_2. \quad (7) $$

We may now consider the relationship of $\bar{N}$ and $\bar{N}_2$: There are three possibilities:

(1) If $p_n$ is the same for all values of $n$, equations (4) and (6) are identical. This would be the case if there were no biological or social inheritance of fertility.

(2) If $p_n$ is negatively correlated with $n$—a most unlikely assumption—$\bar{N}$ will be greater than $\bar{N}_2$.

(3) If $p_n$ is positively correlated with $n$—as is most probably the case—$\bar{N}$ will be less than $\bar{N}_2$.

Our formula (4) could be applied as it stands only if data were available not only on the fertile but also on the infertile families in the second generation. But since it is not the absolute but the relative magnitudes of the several values of $p_n$ that affect the result, and since in populations which have been studied there seems to be a fairly high negative correlation between average size of fertile families and proportion of infertile families, it would seem legitimate to take as a first approximation to the relative values of $p_n$ the average sizes of fertile families only, i.e., the families of the parents of the $q_n$ individuals in the sample. It seems likely that such a procedure would indicate a reduction in the apparently rapid rate of decline in family size shown by the studies which we have mentioned.

286

The Journal of Heredity

increased from 27.8 to 28.75, almost one year.

2. Ratio of married women, and percentage of women married. The mean age of married women is not the only factor influencing the crude birthrate to be expected. The number of married women per 100 population is equally important: in 1890 it was 12.7, in 1920, 14.2. This, per se, does not indicate necessarily a higher marriage rate; but it does when we also observe that there were, in 1890, 23.0 women between 15 and 45 out of a population of 100, while in 1920 there were 23.4. Thus in 1890, about 55 per cent of the women were married; in 1920, 61 per cent.

3. Potential Crude Birthrates. What of the net effect of the above changes in the composition of the population upon the crude birthrate which should be expected if individual fecundity remained constant? Since age-specific fertility rates for the United States as a whole are not available, we shall apply Tait's Law to obtain a rough approximation of the effect.* On this basis, the crude legitimate birthrate would be expected to have increased about 10 per cent between 1890 and 1920.

If all women, instead of only married women, be taken as a basis for computation, the expected rate shows a slight decline.

From an examination of the accompanying charts, it will be seen that

## RELATIVE POTENTIAL BIRTHRATE

Symbols the same as in Figure 5. The actual decline in the birthrate has been due either to volitional restriction or to decline in biological fecundity, for the potential birthrate has been on the increase.

the trends for each of the nativity groups have been in the same directions as those for the total population.

This paper does not purport to answer the question whether the average woman at present is marrying later or earlier than the woman of 1890; it indicates that the net effect of whatever changes have taken place in birth, marriage, divorce, and death rates in the past three decades has been to produce a population having a higher potential birthrate than that of 1890; and that this is not due to the change in the age-composition of the whole population.

It follows that any decline in the actual crude birthrate (or indeed, the failure of the birthrate to have increased) must be due either directly to volitional restriction or to a decline in biological fecundity.

*Tait's Law, in general form, is:

$$F_t = k (b-t)$$

in which $t$ = age, $F_t$ = births per 100 married women aged $t$, and $k$ and $b$ are constants. Tait found $b$ = 50 and $k$ = 1.5. These values of the constants were used in computing the rates given in this paper. A very rough computation for rates in the birth registration area of the U. S. in 1922 gives $k$ = 1.3, $b$ = 45. The value assigned to $k$ does not affect the comparisons between rates at different times, so long as $k$ is held constant. Since the value of $b$ varies for different population, but must be held constant for purposes of comparison, any value that may be assigned is somewhat arbitrary.

For an analogous application of Tait's law, see Elderton, E. M., Univ. of London Eugenics Laboratory Memoir No. 19, p. 5. (1914), and Stevenson, T. H. C., in The Declining Birthrate (rept. of National Birthrate Commission, London, 1916, p. 352. Also articles by Yule, Newsholme and Stevenson, in Jour. Royal Statistical Society, vol. 69 (1905).

Figure 7