Evening star., 1933-09-01
GROWTH OF CHILD
VARIES WITH YEARS
Human Beings, Like Plants,
Have Good or Bad "Snrout-
-. ing" Seasons.
BY THOMAS r. HENRY.

Children, like plants, have their good
and bad growing years.
That the average growth Of all the
children of a small city varies signif-
cantly from year to year, for some mys-
terious reason, Is shown in an intensive
statistical analysis of the weights Of
the school children of HagerstoWn, Md,
through a period of seven years, made
by DR.. Carroll E. Palmer of the United
States Public Health Service.
Thus from May. 1922, to May, 1928,
was a good growing year. The same
period for 1924-25 was bad growing
year. But between May, 1926, and
May, 1927 was record growing year.
The children varied in age between
6 and Is years. They were all white
and native born, but the economic
status of the families showed wide varl-
alton. Separate calculations were made
for each age group, and for boys ami
girls.
There is also some evidence that
the weight of person may be affected
by the year of birth, although it does
not appear clearly in the $500 cases
weighed. The same cases, in many
instances, were followed throughout the
seven years and the average growth per
year for the entire period taken as the
normal
Can't Explain Variations.
The same phenomenon appears strik
ingly in the growth of trees, the extent
of which for year is shown by the
width of the ring formed in the wood,
This is so specific that meteOrologists
can ten a good deal about the climate
OF any particular year centuries ago if
Stirr nf do tinO
from that period. 1t also appears in
the growth curves of plants and wild
animals, presumably due to abundance
or scarcity of food.
But why it should appear in chill
dren, carefully shielded from the ad-
verse effects of nature, Public Health
Service scientists cannot explain. So
far as is known, there were no partic
ularly adverse economic conditions in
Hagerstown during the years when the
majority of the city's children sank far
below the average In growth.
During the 1929 period the boys
gained per cent and the girls per
cent more than the average yearly gain
for the entire span. A year later, the
1924-25 period, the boys gained per
cent and the girls per cent less than
their own average. But for 1926-27
the boys gained 5 per cent and the girls
per cent more than their average.
Thus in three successive calendar years
there was a growth variation of GS
much as IS per cent.
The effect of the poor growth year
seemed to be distributed more gener-
ally among all the children than that
OF the good growth years.
Many Influences Found.
Analysis showed that girls born with
in six months of January /, 1915, were
slightly heavier than the average fCr
their age, indicating there may be
good and bad years to be born in. But,
DR.. Palmer points out in his report.
this conclusion is very ten itive since
this particular group was small in
HagerstoWn and probably included
more than the normal number of indi-
viduals normally slightly heavier than
the average.
"It is reasonable to believe" says Dr..
Palmer, that a great number of inter-.
correlated variables are associated with
the observed variation. On the side
of the physical or Genealogical char
acteristics of the different years it is
conceivable that the amount Of sola-
energy, in terms of total hours of sun
shine, hours of cloudiness, amount of
rainfall, average humidity, ETC., is re-
lated to the growth differences. III
connection with the study of such va
riables It would be of interest to deter
mine whether or not the growth of
trees and plants, yields Of grain and
vegetable products, milk yields, egg pro-
duction, etc, show a similar fluctua-
tion.
ION the side Of the socio-economic
characteristics of the years Of observa-
tion it Is reasonable to SuppOSe that
the amount of unemployment, per cap
ita wages of the employed, etc, might
be associated with the growth trends.
Consideration of the possible factors
involved and study of some of them
have convinced me that the variables
concerned are probably closely related
and that it is quite impossible on the
basis of only seven years of observation
to find significant associations. 1t must
be sufficient to point out that statisti-
cally significant differences in annual
weight increments are observed in chill
dren living under what may be con-
siderad normal conditions for normal