th its delicate shade of heliotrope
is now a familiar object in hospital and surgery. But one story is of
special interest because it shows us clearly how Lister, while clinging
to a principle, was ready to modify the details of treatment by the
lessons which experience taught him. It was on the advice of others that
he first introduced a carbolic spray in order to purify the air in the
neighbourhood of an operation. At first he used a small spray worked by
hand, but this was, for practical reasons, changed into a foot-spray and
afterwards into one worked by steam. One objection to this was that the
steam-engine was a cumbrous bit of apparatus to carry about with him to
operations; and Lister all his life loved simplicity in his methods.
Another was that the carbolic solution, falling on the hands of the
operator, might chill them and impair his skill in handling his
instruments. Lister himself suffered less in this way than most other
surgeons; with some men it was a grave handicap. The spectators at a
demonstration found it inconvenient, and in one instance at least we
know that the patient was upset by the carbolic vapour reaching her
eyes. This was no less a person than Queen Victoria, upon whom Lister
was called to operate at Balmoral in 1870. About the use of this
apparatus, which was an easy mark for ridicule, Lister had doubts for
some time; but it was not the ridicule which killed it, but his growing
conviction that it did not afford the security which was claimed for it.
He was hesitating in 1881; in 1887 he abandoned the use of the spray
entirely; in 1890 he expressed publicly at Berlin his regret for having
advocated what had proved to be a needless complication and even a
source of trouble in conducting operations. In adopting it he had for
once been ready to listen to the advice of others without his usual
precaution of first-hand experiments; in abandoning it he showed his
contempt for merely outward consistency in practice and his willingness
to admit his own mistakes.

It was at Glasgow that Lister made his initial discoveries and conducted
his first operations under the new system. It was in the Glasgow
Infirmary that he worked cures which roused the astonishment of his
students, however incredulous the older generation might be. He had
formed a school and was happy in the loyal service and in the enthusiasm
of those who worked under him, and he had no desire to leave such a
fruitful field of work. But