ht bronchus is more frequently
invaded than the left because of the following factors: I. Its greater
diameter. 2. Its lesser angle of deviation from the tracheal axis. 3.
The situation of the carina to the left of the mid-line of the
trachea. 4. The action of the trachealis muscle. 5. The greater volume
of air going into the right bronchus on inspiration.

The middle lobe bronchus is rarely invaded by foreign body, and,
fortunately, in less than one per cent of the cases is the object in
an upper lobe bronchus.

_Spontaneous Expulsion of Foreign Bodies from the Air Passages_. A
large, light, foreign body in the larynx or trachea may occasionally
be coughed out, but the frequent newspaper accounts of the sudden
death of children known to have aspirated objects should teach us
never to wait for this occurrence. The cause of death in these cases
is usually the impaction of a large foreign body in the glottis
producing sudden asphyxiation, and in a certain proportion of these
cases the impaction has occurred on the reverse journey, when cough
forced the intruder upward from below. The danger of subglottic
impaction renders it imperative that attempts to aid spontaneous
expulsion by inverting the patient should be discouraged. Sharp
objects, such as pins, are rarely coughed out. The tendency of all
foreign bodies is to migrate down and out to the periphery as their
size and shape will allow. Most of the reported cases of bechic
expulsion of bronchially lodged foreign bodies have occurred after a
prolonged sojourn of the object, associated which much lung pathology;
and in some cases the object has been carried out along with an
accumulation of pus suddenly liberated from an abscess cavity, and
expelled by cough. This is a rare sequence compared to the usual
formation of fibrous stricture above the foreign body that prevents
the possibility of bechic expulsion. To delay bronchoscopy with the
hope of such a solution of the problem is comparable to the former
dependence on nature for the cure of appendiceal abscess.

We do our full duty when we tell the patient or parents that while the
foreign body may be coughed up, it is very dangerous to wait; and,
further, that the difficulty of removal usually increases with the
time the foreign body is allowed to remain in the air passages.

_Mortality and morbidity of bronchoscopy_ vary directly with the
degree of skill and experience of the operator, and the conditions for
which