the glottis is chiefly affected during the act of sobbing.
This sound is heard "at the moment when the inspiration conquers
the resistance of the glottis, and the air rushes into the chest."
But the whole act of respiration is likewise spasmodic and violent.
The shoulders are at the same time generally raised, as by this
movement respiration is rendered easier. With one of my infants,
when seventy-seven days old, the inspirations were so rapid
and strong that they approached in character to sobbing; when 138
days old I first noticed distinct sobbing, which subsequently
followed every bad crying-fit. The respiratory movements are partly
voluntary and partly involuntary, and I apprehend that sobbing
is at least in part due to children having some power to command
after early infancy their vocal organs and to stop their screams,
but from having less power over their respiratory muscles,
these continue for a time to act in an involuntary or
spasmodic manner, after having been brought into violent action.
Sobbing seems to be peculiar to the human species; for the keepers
in the Zoological Gardens assure me that they have never heard
a sob from any kind of monkey; though monkeys often scream loudly
whilst being chased and caught, and then pant for a long time.
We thus see that there is a close analogy between sobbing
and the free shedding of tears; for with children, sobbing does
not commence during early infancy, but afterwards comes on rather
suddenly and then follows every bad crying-fit, until the habit
is checked with advancing years.


[11] `De la Physionomie,' 1865, p. 126.

_On the cause of the contraction of the muscles round the eyes