110 
J. GERTH, JR. 
to agriculture. We will next look somewhat closer at the causes 
of sporadic abortion, in order to get a better understanding of 
the aetiology of infectious abortions. It is know T n that all stimuli 
producing a contraction of the uterus, can finally lead to abortion. 
A very important fact is, that the uterus, even in the various 
stadia of pregnancy, possesses a different degree of irritability, and 
that non-grovid uterus can only be contracted through strong irri¬ 
tations, whilst the least irritation is sufficient to produce this effect 
by a grovid uterus. It is known that the irritability of the uterus 
proportionally increases as pregnancy advances, and that these irri¬ 
tations, which are always found in the way, finally lead to con¬ 
tractions of the uterus and natural birth. We know that the irri¬ 
tability of the uterus increases with the temperature of the body, 
certainly within physiological limits, and decreases with decrease of 
the temperature. It is also known that the contraetibility of the 
uterus can be annulled through carbonized blood. From the pre¬ 
ceding, it may easily be understood that under all circumstances, 
where the temperature of the body is continually being increased, 
and where blood of the above mentioned character is being formed 
at the same time, abortion is liable to occur. 
By quick movements of animals in pregnancy, by continual 
overwork, and in morbid conditions, where the excretion of car¬ 
bonic acid is rendered more difficult, and where a higher tempera¬ 
ture is existing, the case is the same; for example, by phthisis, in¬ 
fluenza, etc. The frequent abortions following these conditions 
are easily explained. Colic and tympanitis are also often followed 
by abortion. Its origin is not so much dependent upon the large 
expansion of the intestine as in the retention of carbonic acid. It 
may be mentioned that the respiration in this case is doubtlessly 
rendered very difficult through the considerably expanded abdo¬ 
men by pregnant animals, and would be rendered still more diffi¬ 
cult where it is not counteracted by the powerful heart action and 
general hyperaemia. 
Among pasturing animals, abortion is often produced to a 
large extent by their partaking of frosted grass, frozen potatoes, 
Ac. Evidently the cause of this phenomenon is influenced by 
cold. Herrmann and Gantz have proved that severe anaemia of 
