how true also is it that one half the world does not know,
and does not care, what the other half suffers.

Epilepsy shows every gradation, from symptoms which cannot be described in
language, to severe _grand mal_. Gowers says: "The elements of an epileptic
attack may be extended, and thereby be made less intense, though not less
distressing. If we conceive a minor attack that is extended, and its
elements protracted, with no loss of consciousness, it would be so
different that its epileptic nature would not be suspected. Swiftness is an
essential element of ordinary epilepsy, but this does not prevent the
possibility of deliberation."

In Serial Epilepsy, a number of attacks of _grand mal_ follow one another,
with but very brief intervals between. Serial epilepsy often ends in

_Status Epilepticus_, in which a series of _grand mal_ attacks follow one
another with no conscious interval. The temperature rises slowly, the pulse
becomes rapid and feeble, the breathing rapid, shallow and irregular, and
death usually occurs from exhaustion or heart-failure. Though not
invariably fatal, the condition is so very grave that a doctor must
instantly be summoned. Nearly all victims of severe, confirmed epilepsy (25
per cent of all epileptics) die in _status epilepticus_.

Jacksonian Epilepsy, named after Hughlings Jackson, who in 1861 traced its
symptoms to their cause, is not a true epilepsy, being due to a local
irritation of the cortex (the outermost layer) of the brain.

There is usually an _aura_ before the attack, often a tingling or stabbing
pain. The chief symptoms are convulsions of certain limbs or areas of the
body, which, save in very severe cases, are confined to one side, and are
not attended by loss of consciousness.

The irritation spreads to adjacent areas, as wavelets spread from a stone
thrown into a pond, with the result that convulsions of other limbs follow
in sequence, all confined to one side.

As every part of the brain is connected to every other part by "association
fibres", in very violent attacks of Jacksonian epilepsy the irritation
spreads to the other side of the brain also, consciousness is lost, the
convulsions become general and bilateral, and the patient presents exactly
the same picture as if the attack were due to _grand mal_.

All degrees of violence are seen. The convulsions may consist only of a
rapid trembling, or the limb or limbs may be flung about like a flail.

Jackson sa