r of much importance. Otherwise,
as a general rule, the recollection sinks, and appears to be utterly
drowned in the waters of Lethe.

The instances, according to my personal experience, are very rare,
and even those are not very satisfactory, in which some event
recalls a memory that had lain _absolutely_ dormant for many years.
In this very series of experiments a recollection which I thought
had entirely lapsed appeared under no less than three different
aspects on different occasions. It was this: when I was a boy, my
father, who was anxious that I should learn something of physical
science, which was then never taught at school, arranged with the
owner of a large chemist's shop to let me dabble at chemistry for a
few days in his laboratory. I had not thought of this fact, so far
as I was aware, for many years; but in scrutinising the fleeting
associations called up by the various words, I traced two mental
visual images (an alembic and a particular arrangement of tables and
light), and one mental sense of smell (chlorine gas) to that very
laboratory. I recognised that these images appeared familiar to me,
but I had not thought of their origin. No doubt if some strange
conjunction of circumstances had suddenly recalled those three
associations at the same time, with perhaps two or three other
collateral matters which may be still living in my memory, but which
I no not as yet identify, a mental perception of startling vividness
would be the result, and I should have falsely imagined that it had
supernaturally, as it were, started into life from an entire
oblivion extending over many years. Probably many persons would have
registered such a case as evidence that things once perceived can
never wholly vanish from the recollection, but that in the hour
of death, or under some excitement, every event of a past life
may reappear. To this view I entirely dissent. Forgetfulness
appears absolute in the vast majority of cases, and our supposed
recollections of a past life are, I believe, no more than that
of a large number of episodes in it, to be reckoned perhaps in
hundreds of thousands, but certainly not in tens of hundreds of
thousands, that have escaped oblivion. Every one of the fleeting,
half-conscious thoughts that were the subject of my experiments,
admitted of being vivified by keen attention, or by some appropriate
association, but I strongly suspect that ideas which have long since
ceased to fleet through the b