Sir Joseph Hooker’s “ Himalayan Journal,” 1st edition, vol. ii. page
4 0 7 “ From a multitude of desultory observations, I conclude that,
at7400 feet, 125'7°, or 67'0° (Fahrenheit’s scale) above the temperature
of the air, is the average effect of the sun’s rays on a black bulb
thermometer. The effect is'much increased by elevation. At 10,000
feet, in December, at 9 am., I saw the mercury mount to 132° Fahr.,
while the temperature of the shaded snow was 22° Fahr. At 13,000
feet, in the following month, at 9 a.m., I saw it stand at 98°, with a
difference of 68'2°; and at ten o’clock, at 114° (Fahr.), with a difference
of 81-4°, whilethe thermometer placed onthesnow had fallen, at sunrise,
to 0'7 of a degree, or 31-3° below the freezing point, on Fahrenheit’s
scale.” Tyndall’s explanation of this phenomenon is as follows
“ These enormous differences between the shaded and the unshaded air,
and between the air and the snow, are no doubt due,” as I mentioned
in my original note, “ to the comparative absence of moisture at these
elevations. The air is incompetent to check either the solar or the
terrestrial radiation, and hence the maximum heat in the sun and the
maximum cold in the shade must stand very wide apart.” Quite dry
air acts, in fact, towards solar heat as a vacuum and the heating of the
atmosphere is all due to the presence of aqueous vapour in i t ; as quite
dry air transmits heat-rays without itself being warmed at all. This
was proved by Tyndall at the last B.A. at Swansea. Such observations
as these have been recorded by Sir J. Herschel, Dr. Livingstone, and
numerous other eminent men, and I could quote page after page of
similar observations in direct support of what I have stated.
The remainder of the letter in question needs no explanation or
refutation from me, as its fallacy is so palpable that the most hasty of
your readers will already have discovered the mass of errors of which
it is composed. In conclusion, I may recommend the “ Header of
Colburn’s New Monthly ” to invest a shilling in the purchase of an
elementary primer of physics and astronomy, where he may learn
the rudiments of a science about which neither himself nor, indeed,
Mr. Joshua Prusol appear to have any real practical knowledge.
I t was a little family joke against him, poor fellow,
th a t he was “ discharged ” from this country paper.
His “ honorarium ” was small, and he received it irregularly.
Desiring to supplement some drafts of mine,
on account of certain chemical apparatus which he had
bought, he wrote for the salary due to him. No reply.
He wrote again. Then Came his money and his dismissal.
I noticed a flush of anger upon his face for a
moment; it passed into a smile as he said, “ I have
got my cheque and my discharge ! Well, there is work
one can do for nothing, but not that sort of work.” I
told him that small troubles of this kind were often
more irritating than great ones. “ Little things will
never bother me,” he said, putting his cheque into his
pocket and his letter into the fire. “ One hasn’t time,
eh, p a ? ” And I don’t think the little concerns of life
ever did trouble him. As for time, he had none to
waste; when he was not working, he was playing, and
he did both with all his might.
VI.
At about this period he wrote a series of some twenty
sketches of the careers and work of living men of
science for the Biograph. Among his letters are
pleasant epistles from several of the subjects of his
papers, all pointing to the fact that he took pains with
his work. He was not vague about dates, nor uncertain
in his figures; he was very clear in his summaries of
scientific facts, and he had an educated appreciation,
and showed it unconsciously, of the labours he discussed
and described. If he had done nothing else besides
literary work at this time, he would have been entitled
to respect; but these items of industry I am mention-;
ing were accomplished in addition to his successful
studies and examinations at South Kensington and the
School of Mines. He contributed to' Bradstreets (an
American journal of high repute) several articles of an
economic character, embracing such subjects as dye-
works, aniline dyes, glass making, and gold and silver.