44
thing to decide on the shape of the spirilloids in movement. The way they wriggle
about and constantly pass out of focus renders their delineation very trying to the
patience, and any representation of them on paper purely diagramatic. The dried and
stained specimens (especially the magenta ones) are most beautiful objects. I think
the figures in some text-books of the spirillum, like a huge corkscrew, must be purely
imaginary and deduced from ideas formed of what the parasite in motion would
be like if it were sufficiently enlarged. If such be the case, they are very apt to
mislead and require immediate correction in accordance with the latest proved facts.
We shall hereafter consider the parasite further.
4. The thermometer is the guide which ranks next to the microscope in value for
purposes of diagnosis. The tracings which I have obtained by careful personal investi-
gation for a complete month and by reliable records under my immediate supervision
for a much longer time are beautifully illustrative of the effects of the disease-producing
organism on the thermogenic centre. When an inoculation has taken, the mercury
rises to 106° or 105° Fahrenheit, generally in a gradual manner and with one fall in its
course usually on second day ; the evening temperature is exaggerated in relation to the
morning, whereby the diurnal oscillations are rendered much greater than in health.
On third, fourth, and fifth days the reading is high and gradually increasing, so that
usually on the evening of the fifth day of exacerbation the crisis is reached; a rapid fall
then ensues, so that on seventh morning the temperature is low and so remains for two
or three days until the next rise. In typical cases there is a slight check to the abrupt
fall on the evening of the sixth day. Thus a stage of the disease is completed, and
these stages, varying in length from seven to ten days, may occur again and again,
varying in number from three or even fewer to, it may be, as many as seventeen before
death. The phase of low temperature reading cannot be designated " fever-free,"
because the line seldom falls to the normal; it may, however, descend even lower, and
such great oscillations indicate usually the approach of the fatal result. The
maximum reading is sometimes 107° Fahrenheit or even more, but usually not quite so
high. A rise above 108° Fahrenheit indicates speedy death. There are thus two
conditions under which death occurs—the very high temperature (in one case I obtained
a reading of 110° Fahrenheit) and the very low; the latter is most frequent and found
generally in prolonged cases. There is no other disease of lower animals in which the
thermographic tracings are so neat and so specially significant. The pulse records
when reproduced in the form of a tracing give us ample confirmation of the relapsing
character of the fever as shown by the variations in animal heat. As the finger
generally used in taking the pulse is less delicate as a medical test than the thermo-
meter, it does not suffice for slight variations in tone or volume of the artery, but by
accurate record of the number of the pulse beats we can " steady," so to speak, the
results obtained by the highly 1 sensitive thermometer and prevent our being led
astray by the numerous minor surrounding influences which affect the temperature of
the body. Suffice it to say that the tracing from the number of pulse beats resembles
that from thermometer readings, that the pulse is sometimes dicrotous, often very
small and difficult to take, but sometimes fuller and stronger than might be anticipated
from the debilitated state of the animal. Records of the frequency and nature of the
breathing are much less valuable. Auscultation and percussion indicate no abnor-
mality of the lungs and pleura until within a few hours before death. When the fever
is severe the breathing is quickened, and I have observed cases of double expiration
and others of double inspiration. A labored oppressed breathing is generally an
immediate precursor of death; this grave symptom is associable with loss of breathing
sounds at the lower part of the chest and also with a mucous râle indicative of pulmo-
nary congestion, hydrothorax, and accumulation of froth in the trachea and bronchi.
In addition to the symptoms already enumerated, I have noted others, in the cases
under observation, which probably have resulted from accidental complications;
such are coughing, extreme nervousness, oedematous swellings around the arms, and
external generative opening of the female due to excessive straining for removal of
faeces after the animal is down; also the formation of simple abscesses, presenting no
specific characters, in so far as I could determine, on the skin. In some cases slight
anaemic pulsation of the jugulars and cardiac murmurs due to the same cause may
be noted.