Firstly, To a complete trial of this practice, it
might be necessary to fill apartments with
modified air. Even unfavourable conclusions
should be established in such a manner as to
leave no regret behind; and persons of enlarged
views will, I suppose, assent to an
observation of Mr. Thomas Wedgwood, 'That
it is worth while to expend the specified sum
in order to assure ourselves that elastic fluids
will not be serviceable as medicines.' Secondly,
It would be desirable to have the means of
applying this practice to animals—as dogs
and horses—labouring under dangerous or
fatal disorders. Thirdly, We might carry on
physiological investigations of longer duration
and greater extent, than have ever yet been
devised, with a view to discoveries, applicable
to the practice of physic. Fourthly, As all
imaginable precautions would be taken to
authenticate facts and give them publicity, a
large quantity of matter for reflection, if not
of knowledge immediately useful, would be
thrown into circulation. Fifthly, Observations
on private patients may suggest modes
of applying air, not easily practicable but in
an appropriated building." This plan of
Dr. Beddoes had no reference to climate; it
did not mean a change of our air or diet, but
the introduction of aëriform medicine. More
or less oxygen, more or less hydrogen, the
addition of any gas or vapour found to have
a medicinal effect when inhaled, was what the
projector contemplated. The manufacture of
the modifying gases was accomplished by an
apparatus invented and furnished from the
Soho Works of Boulton and Watt; James
Watt being a warm supporter of the scheme.
That inhalations of this kind were not in-operative
on the human system, must be from
the nature of things obvious. Ether vapour
was among the remedies employed, and
thinking of this, Dr. Beddoes writes, " If a
species of opium capable of lulling the
excruciating pains of cancer for weeks or months
had been discovered, it would doubtless be
received with avidity by the members of the
medical profession, and with benedictions by
the diseased. But because it is uncertain
whether a complete and permanent cure can
be effected by the application of air, this
treatment is not only neglected, but resisted."
Ether vapour since that time has been received
with benedictions; and the day may
come when many other medicinal "airs" will
become known as blessings by the sick. It
is impossible not to be amused—though there
is no ridicule in our amusement—at the
philosophic enthusiasm with which Watt
laboured at the question. Here, for example,
is a notion found among a string of hints:—
"If it be certain that butchers are exempt
from phthisis, putrid animal effluvia may be
useful; and if the matter which constitutes
the smell, be not the useful part, it may be
corrected by powder of charcoal, which does
not otherwise hinder the progress of putrefaction."
Such a notion of a Sanatorium
could be carried out now only by the London
Corporation, and upon the site of Smithfield.
Here is a complete note from Watt to Dr.
Beddoes, which is one of the most delicious
examples extant—not being fiction—of a
philosopher astride upon a hobby.

"I have just made an air, which, as it has
great powers, may, for aught I know, have
great virtues; my experience extends only to
its bad qualities—Pyro-sarcale. I put 2oz.
of lean beef in the fire-tube, and obtained, by
mere heat, 250 cubic inches of air, highly
fœtid, like an extinguished tobacco-pipe;
inflammable, with a very blue flame; little
diminished by lime and water. Pyro-hydro-sarcate:
on adding water to the red-hot charcoal
of this beef, I obtained 600 cubic inches
of air, with a fœtor not so bad as the other;
burning with an orange-coloured flame;
losing not one-thirteenth in lime-water. The
smell of the first made me sick, though I did
not inspire any purposely, and not above one-third
of the quantity mentioned was let loose
in my laboratory, and three doors and a
chimney were open; we were, however,
obliged to leave the place for some time. The
Pyro-hydro-sarcate seemed to possess the
same property, but was more cautiously
treated; I was giddy all the afternoon.
Pyro-comate: Next day 2oz. of woollen rags
were put into the tube; they gave, by mere
heat, 800 cubic inches of air, fœtid, though
not so offensive as the other; burning with
a deep blue flame; not tried with lime and
water. Pry-hydro-comate, by addition of
water to the red-hot charcoal, gave above
one-and-a-half cubic foot of air, fœtid, but more
like vol. alkali in smell, burning with a yellow
flame; losing one-fifth by washing with lime
and water; part was undoubtedly alkaline
air, and absorbed by the water; the water in
the refrigeratory was strongly impregnated
with fœtid vol. alkali. Though none of
either of the airs was inspired that could be
avoided, I had a slight, though uncommon
nausea, attended with some elevation of the
spirits, all that evening, but no heat or thirst;
in short, it was very like the effect of the
fumes of tobacco on an inexperienced person.
In bed I was restless, though without pain or
particular uneasiness. I could not sleep.
Next day the nausea, and some giddiness,
continued, or rather increased, and a headache
came on. The uses of this air, if it has
any, I leave you to find out. I think I shall
have no more to do with it, or with animal
substances. One may discover, by accident,
the air which causes typhus, or some worse
disorder, and suffer for it.
"October 7, 1794. JAMES WATT."

Experiments on medicated air appear to
form, however, no part of the scheme of Mr.
Paxton. That is a matter to be left entirely
to the medical profession. To provide glass
promenades attached to buildings, well
ventilated, dried, warmed and regulated to a given