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OBSERVATIONS ON INFLUENZA IN HORSES. 
for five successive epochs to trace back the years most remarkable 
for the prevalence or fatality, or for both, of influenza among horses 
to intervals of three years between each, or to its more than usual 
prevalence or fatality every fourth year. Should this fact be found 
to hold good — and, so far as my present sources of information go 
it is not gainsaid- we may expect visitations of influenza of a 
more alarming kind than ordinary in the years to come, 1848- 
1852, 1856-1860, &c. 
The influenza of 1828 was most prevalent during the spring of 
that year ; that of 1832 also during the spring ; that of 1836 
during the spring, summer, and autumn ; that of 1840 during the 
spring; and that of 1844-5 during the autumn and winter. Au- 
tumnal and winter epidemics have in general proved more alarm- 
ing and fatal than spring and summer visitations. 
That young horses, on several accounts — their greater suscepti- 
bility, their teething, their having strangles, &c. — are more likely 
to take influenza (and especially when the disease assumes a 
catarrhal form) than others, everybody knows ; but the subject of 
all others most predisposed to take the disease is — or at least has 
been during the late influenza — the horse having a five-year-old 
mouth, i. e. being either rising or past five. Of the late influenza 
I have had sixty-four cases, and out of them forty have been 
horses presenting five-year-old mouths. 
Although the influenza of one year will probably differ from 
that of another year, not only in intensity and prevalence, but in 
its symptoms as well, according as the nasal passages or throat, or 
thoracic or abdominal organs, or brain and nervous system, &c., 
are most affected by it, still is there to be observed sufficient uni- 
formity in its attacks to admit of our recognising it at any season 
and in any situation, and the following symptoms will, I believe, 
invariably enable us to do so : — 
Anorexia or failure of appetite ; languor or dulness, and lassi- 
tude or disinclination to move, both arising from evident depres- 
sion and debility ; gravedo or heaviness about the eyes, drooping 
of the eyelids, and hanging the head under the manger ; rigor or 
cold and shivering fit, succeeded by a hot fit, and fever of a low 
and nervous character ; increase of pulse ; mouth hot and moist ; 
tongue dry and rough ; coat roughened and void of gloss; extre- 
mities cold; soreness, often extreme, of throat, and difficulty of 
deglutition; cough; prostration of strength, the patient straddling 
and staggering or reeling in his walk ; membranes of the nose, mouth, 
and eyes, reddened, and tinged with yellow; sparing defluxion of 
yellowish matter from the nose ; indications of pain in the head ; 
puffiness or swelling of the eyelids, and consequent partial or com- 
plete closure of them ; intolerance of light ; lachrymalion or oozing 
