is later attacks with anger, worry, embarrassment, even the
excitement of watching a play at the theatre, was noted again and
again. In Javal's case, the attack fatal to one eye came at the
culmination of an exciting electoral campaign. The other eye was
stricken at the termination of the Dreyfus case, in which Javal was
intensely interested. There seems to be a special liability to glaucoma
among those residing at high altitudes, best explained by nerve
influence. The frequency of glaucoma among Jews may be due to a small
cornea, as suggested by Priestley Smith; but it is quite as reasonable
to connect it with a racial excitability or nervous instability. More
definite knowledge of the nervous mechanism concerned in the regulation
of intra-ocular pressure and the production of glaucoma is much needed.

_Alterations of Fluids and Tissues_

The influence of increased affinity of the tissues for fluid has already
been referred to. That a similar obstacle to the escape of fluid from
the eyeball might be due to a change of character in the fluid, is a
conception that has been entertained as a working hypothesis, and much
experimental and analytical work has been done to test its correctness.
This work has been so slightly related to practical ophthalmology, and
so contradictory in its results that alterations in the fluids can only
be regarded as a possible etiologic factor. Glaucoma secondary to
intra-ocular hemorrhage, operations on the lens or its capsule, or
severe nutritional disturbance may be capable of such explanation.

_Different Kinds of Glaucoma_

A better grasp of the etiology of glaucoma may be attained by
considering separately various types of cases; although perfectly
typical cases may be rare; and cases of mixed type and etiology much
more frequent.

Simple glaucoma has been recognized as closely related to atrophy of the
optic nerve with deep excavation. No line of demarcation can be drawn
between them, except by reserving the term of glaucoma for cases that
depart from the pure type, terminating in glaucoma of some other kind,
which is no more significant than the passage of a conjunctivitis into a
keratitis, or an iritis into a glaucoma. Cases of simple glaucoma do run
their course of many years to complete blindness, or to death, without
exacerbations, inflammation, or characteristic pain. In such cases the
intra-ocular tension does not rise suddenly; and it may be little or not
at all elevate