I came across a 1917 publication (full text freely available at Google Books) in which Hrdlicka outlines his rationale for studying "Old Americans" and some of his preliminary findings. More complete findings were published in 1925 in The Old Americans.
The Old White Americans
Ales ̆ Hrdlic̆ka.
Published: Washington DC : [s.n.], 1917.
Series: Proceedings of the International Congress of Americanists ; 19th, December, 1915.
FROM early in the seventeenth century the Temperate Zone of North America has been receiving successive contingents of the white race who have settled on the available land and multiplied and spread, thus forming the American nation. These newcomers were derived from Europeans of various physical types, ranging from the prevalently tall, blond, blue-eyed dolichocephalic Northmen to the mostly dark-haired, brown-eyed, medium tall, and brachy- cephalic Celts; and according to all indications they were, as a lot, physically, and especially mentally, above the average of their parent groups, for both the pioneers, whose ideals were religious and political liberty, and who would brave the dangers of the long sea journey with the hard conditions of life in the New World, as well as those commonly classed as adventurers, can well be assumed to have been on the whole men with a surplus of mental power and physical energy.
The men, and the women who accompanied them and who were probably of similar good material, encountered in large measure new environments and lived a new life. They reared their families under these changed influences, and the children accommodated themselves completely to the new conditions—they became Americans. Then followed intermarriage, both within and without the various contingents that reached this land, and the original heterogeneity slowly gave place to a blend which constituted the body of the rising nation.
How successful this new conglomerate proved to be, morally, intellectually, in defense and otherwise, are matters of history. It is certain that there was no loss of the original endowments; and also that there resulted in the course of time a considerable approach to unification of all those characteristics of mentality and behavior which are most readily subject to adaptation. It may be safely said that so far as outward manifestations are concerned, the descendants of the Old Americans constitute today a fairly easily separable strain of white people, which is no longer English, Dutch, French, or Irish, but American.
In view of these interesting facts anthropology for a long time has been confronted with the question, Have there also taken place in the descendants of the Old Americans physical changes which produced, or tend to produce, a separate sub-type of the white people?
[. . .] Possibly even in some important respects the type has already passed its zenith, as would seem to be indicated by the lowering birth-rate among its latest representatives, a rate now hardly sufficient in many districts to keep up the numbers of the Old Americans. And how will the type, if it exists, be affected by the growing mixture with whites of recent immigration? Would it be well to try to keep it pure—have the Old Americans marry only among Old Americans—or is new blood desirable?
It is well known that such nationalities as the French, English, German, and others possess, notwithstanding their mixed and relatively recent origin, distinctive physiognomy and other physical features by which in a large majority of cases it is possible to segregate both men and women who belong to them, and the claim has often been made that much the same is true in relation to the Americans. Writers and illustrators have made frequent efforts to define this hypothetical American type, and have even arrived at certain crystalized conceptions, such as "Uncle Sam", the "American girl", and the "American young man", though inconsistently leaving out the remaining periods of life. The Southerner in particular, and the Yankee, as well as the Westerner, a're believed each to have distinctive characteristics by which in the majority of cases they can readily be identified; yet at the same time these "types" are supposed to differ from each other so that any one of wider experience can readily distinguish them. Writers who attempt to define the American physical type do so generally without entering into embarrassing particulars; and the artist either follows certain famous or admired individual types or creates abstract conceptions of what he would have as Americans. Suggestions have even been advanced by some, who might have been expected to know better, that the American type is approaching that of the American Indian, the idea being presumably that the American environment produced the Indian and that it would in due time shape other peoples here to the same mold. Finally, certain scientific reports on the physical changes of Jewish and Italian children in this country appeared to show that the type of the immigrant changed with remarkable rapidity.1 Were this true, the formation of a new, more homogeneous American type ought to be a question of but a few generations, and the type should be already well advanced toward maturity among the descendants of the oldest American families. Unfortunately, however, although under good direction, the examinations on which these results were based were made by college students and not by trained anthropologists; the grandparents and parents of the supposedly changing children were not examined, nor were the children themselves studied at different periods of development; and no data have been given on the important and often significant variations in the children of individual families; so that it is not certain whether the differences the Jewish and Italian children seemed to show from the general type of their nationality or group were not perhaps fortuitous, or hereditary, and thus of pre-American origin.
The above uncertainties can properly be met in but one way, and that by anthropological observations on normal living representatives of the oldest American families, carried on under favorable circumstances and with the greatest possible care and precision. Such a test the writer decided to apply, so far as it might be in his power; and with this view arrangements were made, in the fall of 1912, in the anthropological laboratory of the United States National Museum, for a series of investigations which should extend to at least 300 healthy adult descendants from old American families. Since that time, save for interruptions due to other demands on the writer's time, the work has been progressing slowly. The number of subjects stated, 150 men and 150 women, is regarded by the writer as the smallest number which in a fairly uniform group would cover the more important individual variations in the group and thus give a reasonably clear notion of the type. To make certain that only those would be included in the series whose families have long been subject to the effects of the American environment, it was decided to examine only those who on both sides were American for at least three generations; in other words, those whose parents and all grandparents were born in this country. As to locality, Washington was recognized as the most suitable for the study, for among those settled here as well as among visitors there are Americans from all parts of the country. The measurements and tests, finally, were to be sufficiently thorough to show clearly the physical type of those examined, but involve only a minimum of inconvenience to the subject and a minimum of exposure of the body. To avoid including those not fully developed and the decrepit, the age limits were set at from 24 to 60 years; otherwise there was no selection. [. . .]
As a total result of the efforts made there have been examined to date 140 men and 135 women, including representatives of some of the very oldest and best American families. The conditions of the examination have been ideal: a well-lighted laboratory, the best of instruments tested by standards, no haste, and every subject dealt with with all due care by the writer himself; the possibilities of error, therefore, it is safe to say, have been reduced to the minimum, and the data obtained may claim more than ordinary confidence. They are presented here in preliminary form, yet even thus they are of considerable interest.
The present report will deal, for the sake of easier presentation of the results, with the first 100 men and 100 women who were measured. The data will be given in brief form only, detailed discussion being reserved until the work shall have been completed. The results will doubtless be modified somewhat by the additional number of subjects to be examined, yet on the whole the changes can not be expected to be very material and the data as here presented may already be regarded as fairly definite. [. . .]
Besides the individual variations, certain marked differences will be seen to appear in both the physical and the physiological status between the two sexes. On the whole, it may be said that the male representatives of the Old Americans are excellent specimens of humanity, and there are also physically splendid individual women; but a certain proportion of the latter sex shows a physical development, especially in the upper part of the body, which leaves more or less to be desired. It seems, however, that this is largely a result of long-lasting defects in the proper rearing of female children from the physical standpoint rather than a matter of heredity, and that conditions in this respect are much improved in the present generation of young women. [. . .]
The head among the Old Americans is in many cases remarkable for its good development. This is particularly noticeable in the males, as will be seen from the following tables, especially from that showing the cephalic module, or mean diameter of the head. It will be interesting to note in this connection that among twelve groups of male immigrants from Europe measured within the last two years at Ellis Island under the writer's direction, and comprising together more than 500 individuals, not one group equals in this respect the Americans, the closest approach being noted in the Irish, English, Poles, and North Italians. [. . .]
The study of the actual representatives of the oldest American families has proved throughout one of absorbing interest. The results, however, may prove quite sober and disappointing to those inclined to expect sensational revelations. Nevertheless, they will be valuable both to science and in application. They show quite clearly that no definite, already formed, strictly American type or
sub-type of the whites as yet exists; and as intermarriages of the Old Americans with more recent elements in this country are rapidly becoming more numerous there seems no chance for the formation of something like a separate American type of population, at least within many centuries.
The examinations have shown in many instances a remarkable persistence of heredity characters and their strong individuality, as we may express it, with slow, irregular, unwilling yielding to a complete and permanent fusion with other characters of the same class.
Yet there are indications that some progress has been made toward such a fusion, and that if the Old American families could be kept in full vitality and free from intermixture with newer elements for several more centuries, there would eventually come into existence in this country a real separate sub-type of white people, which would possess numerous if not great distinctive characteristics from the European whites and would be strictly American.