S. Hansen.Biology and Eugenics.25
he is right, as it is clear that the increase cannot have continued in this way
for a long time. The stature of North Europeans was in still earlier times
certainly not much below that of the present day. Measurements of skele
tons from prehistoric times have sufficiently proved, that the stature has
not changed sensibly in the last two thousand years or more, although it
may have oscillated periodically about a mean somewhat different in the
various countries.
It is the agencies alternately improving or impairing the racial qualities
of man which have to be studied, but this is not possible until we possess a
thorough knowledge of the racial qualities, and such knowledge is still
far away. We only need to ask whether the mean weight of the new-born
child is increasing or not to see this. What is the mean weight of the new
born child? We do not know. For British infants Pearson gives the
following averages :—
Male ............................. 7.301+.024 lb.
Female ............................. 7.073+ .021 lb.
This statement is undoubtedly the most accurate available for the present
time; compared with that of the Anthropometric Committee (Final Report,
p. 33, and Table XV.) it indicates the considerable increase of 0.18 lb.
for the male and 0.13 lb. for female infants or 82 and 59 grams respec
tively in about 20 years. These infants, however, are born in charitable
institutions of London and Edinburgh, and belong on the whole to the poor,
labouring class. Many of the mothers might have been brought up in the
country, but we do not know whether the relation between the rural and
urban portion is the same in the two periods or not. Still, it is a well-
known fact that the later children of a mother are heavier than the first,
the weight increasing by about 75 grams from birth to birth, and we do
not know how many of the infants are first-born. Nor do we know if all
the infants are really born at the full period of gestation, for it is very
difficult to decide this question.
It is most probable that the average weight of new-born British infants
has increased by about the amounts stated, 82 and 59 grams, and
this improvement might be due to various agencies, partly to better
nourishment, partly to a healthier mode of life during the period of gesta
tion, but the influence of these various agencies has still to be ascertained.
In Denmark the weight has been found to have increased by only 40 grams
in 35 years, although the general improvement in the hygienic and economic
conditions of the mothers has certainly not been less considerable during
this period than in England. We are not quite sure, however, that the
mothers of these children belong to the same social layer now as 35 years
ago. It is not impossible that the inmates of the lying-in hospital are more
frequently married women of the working class, and if that is the case, the
relative number of first-born, less heavy infants, might have been reduced.
All these difficulties sufficiently prove the necessity of collecting still further
