by a movement of the foreign
body plug. In other cases I have found at bronchoscopy, a regular
ball-valve mechanism. Pneumothorax is the only pathologic condition
associated with signs similar to those of expiratory, valve-like
bronchial obstruction by a foreign body.

3. _Partial bronchial obstruction_ by an object such as a nail allows
air to pass to and fro with some degree of retardation, and impairs
the drainage of the subjacent lung. Limitation of expansion will be
found on the invaded side. The area below the foreign body will give
an impaired percussion note. Breath-sounds are diminished in the area
of dullness, and vocal resonance and fremitus are impaired. Rales are
of great diagnostic import; the passage of air past the foreign body
is accompanied by blowing, harsh breathing, and snoring; snapping
rales are heard usually with greatest intensity posteriorly over the
site of the foreign body (usually about the scapular angle).

A knowledge of the topographical lung anatomy, the bronchial tree, and
of endoscopic pathology* should enable the examiner of the chest to
locate very accurately a bronchial foreign body by physical signs
alone, for all the significant signs occur distal to the foreign body
lodgment.

* Jackson, Chevalier. Pathology of Foreign Bodies in the Air and Food
Passages. Mutter Lecture, 1918. Surgery, Gynecology and Obstetrics,
March, 1919. Also, by the same author, Mechanism of the Physical Signs
of Foreign Bodies in the Lungs. Proceedings of the College of
Physicians, Philadelphia, 1922.

_The asthmatoid wheeze_ has been found by the author a valuable
confirmatory sign of bronchial foreign body. It is a wheezing heard by
placing the observer's ear at the open mouth of the patient (not at
the chest wall) during a prolonged forced expiration. Thomas McCrae
elicits this sign by placing the stethoscope bell at the patient's
open mouth. The quality of the sound is dryer than that heard in
asthma and the wheeze is clearest after all secretion has been removed
by coughing. The mechanism of production is, probably, the passage of
air by a foreign body which narrows the lumen of a large bronchus. As
the foreign body works downward the wheeze lessens. The wheeze is
often so loud as to be heard at some distance from the patient. It is
of greatest value in the diagnosis of non-roentgenopaque foreign body
but its absence in no way negates foreign body. Its presence or
absence should be recorded in eve