l turn blue if it is alkaline) ten grain
doses of benzoate of ammonium three (3) times a day are often useful.

NERVE TUMORS (Neuroma).--A morbid increase in the tissue-elements of the
peripheral (the external surface) nerves.

Varieties. True and False Nerve Tumors.--True nerve tumors (neuromata) are
composed of nerve-fibres provided with a medullary (marrow) sheath or of
nerve tissue; false nerve tumors are composed of other structure than
nerve tissue, are usually of secondary origin, extending to the nerve from
nearby structures.

Symptoms.--The true nerve tumors may be hereditary or due to wounds or
blows and amputation. They may give rise to no symptoms, or may cause
intermittent pain. Pressure increases this pain, when the condition of the
nerve fibre is interfered with. Loss of local sensation and power may
develop. It is sometimes possible to feel the little nodular growths, and
they can be seen when they are superficial. They may give no pain, or they
may become very sensitive. They may become chronic and they are very
liable to do so. Some of them may disappear.

PHYSICIANS' TREATMENT for Nerve Tumor.--The severe forms should be cut
out; others can be let alone.

NEURITIS (Inflammation of the Nerves. Neura-Nerves; Itis-Inflammation.
Inflammation of the Bundles of Nerve Fibres).--Nagel describes it as "an
inflammation of the nerves of an acute or chronic nature, associated with
more or less degeneration, change in the nerve fibrils of the affected
nerves."

[NERVOUS SYSTEM 277]

Causes.--An injury to the nerves, frequent muscular strains, exposure to
cold. Inflammation can extend to the nerve from adjacent inflamed
structures. Pressure can cause it. Fractures of bones cause it by
compression and it is also caused by infectious diseases, such as
rheumatism, typhoid fever, syphilis, etc. In some cases it simply appears
without apparent cause.

When the disease process involves the nerve sheaths and connective tissue
structures in particular, an interstitial neuritis results; when the
disease locates itself in the nerve fibrils it gives rise to
"parenchymatous neuritis" (main part of the nerve is inflamed).

Simple Neuritis.--This means that a single nerve of a group of adjacent
nerve trunks is affected. If a number of nerves are affected at the same
time it is called Multiple Neuritis or Polyneuritis.

Causes.--(a) Exposure to cold. This is a very frequent cause, as for
example, in the facial (fa