lel patie 
| 
Fan. 11, 1883] 
Moreover, if we assume that 19°8 is the velocity at 100 
feet, the velocity at 1,600 feet calculated from it by this 
formula would be almost exactly egwa/ to that observed, 
instead of four times as much as it was when calculated 
= 2. The empirical formula v = 281+ 0°2 J h, 
where z is the velocity in feet per second, and / is the 
corresponding height in feet, gives for the four elevations 
above, results in close agreement with those observed, but 
it would probably fail below 1,600 feet. 
Mr. Stevenson in his first paper uses a formula 
—_ A where Ff are the forces (“ pressures ” I sup- 
BoM 
V 
fon == 
pose is meant by this objectionable word) at the two 
levels corresponding to H and /. 
In his second paper he says he prefers the formula 
- = where P and # are the pressures at the 
—=>—_ = —; 
u h 
two levels to the formula = _ = from which and some 
h 
other remarks it would appear that pressure and velocity 
are considered to vary directly with each other. This is 
a notion which is certainly at variance not only with the 
hitherto generally accepted empirical formule, but is dis- 
tinctly contrary to the results lately deduced by Mr. 
Ferrel from the hydrodynamical theory (see Van Nos- 
trand’s Engineering Magazine, vol. xxvii. p. 141). The 
formula usually found in the text-books is # = ‘00492 v", 
and the one deduced by Ferrel is 
"0027 = 
Da 1+ :0036657 P’ ” 
where P P’ are the barometric pressures at the level under 
consideration and at sea-level respectively, and 7 is the 
temperature in degrees Centigrade ; and though from the 
latter formula it is evident that the pressure at the higher 
levels will be less for the same velocity than below (at the 
height of Mont Blanc, for example, it would be reduced 
by about one-half) there is nothing to lead us to infer that 
ba PP 
vo p 
F H 
If in the formula = - \/ = 
Mr. Stevenson, we make the ordinary assumption that 
FE 
a 
which was discarded by 
2 
- we get the formula which I have already shown 
ap 
gives results which agree closely with the values observed 
by Vettin above 1,600 feet, and which even below this 
height is much nearer the truth so far as can be inferred 
from the slender data employed, than the formula pre- 
ferred by Mr. Stevenson. 
If we take the heights as abscissze, the curve traced out 
by the velocity-ordinates will be much flatter than the ordi- 
nary conical parabola, and at great heights will approxi- 
mate very nearly to a straight line parallel to the axis. 
Ferrel’s increment-term makes it a straight line all through, 
but his formula assumes that the temperature gradient 
between the pole and the equator is the same above as at 
the earth’s surface, it leaves out friction altogether, and 
also supposes the velocity for the same gradient to be the 
same at all heights, whereas according to theory it should 
cos Zz 
increase with the height in the ratio , Where z is the 
angle the wind makes with the isobar, and P is the baro- 
metric pressure at the level under consideration. Not- 
withstanding these omitted factors, of which the first and 
last probably tend to destroy each other, it will be found 
that the addition of the increment corresponding to each 
altitude to the velocity at the surface observed by Vettin 
gives us the following fair approximation to the values 
actually observed, though the calculated values are too 
NATURE 
a 
245 
| small at 1600 feet and too large at 23,000 feet by just 
about the same amount :— 
. Velocity Calculated from 
ates ht- observed, Ferrel’s Formula. 
23,000 59°5 750 
12,800 518 505 
7,200 35 3/50) 
3,800 30°4 28°9 
1,600 374 23°6 
fo) 19°8 
In conclusion, it is evident that, quite apart from the 
meteorological side of the question, more investigations 
like those undertaken by Mr. Stevenson, are urgently 
required to determine the actual rate of increase of the 
velocity at moderate heights, from which a formula like 
the one I have recommended may be deduced, which 
will yield values more within the range of probability than 
those furnished by the one which is apparently supposed 
to suffice for the rest of the atmosphere after we have 
reached the top of the fifty-foot pole. 
E. DouGLas ARCHIBALD 
KRAO, THE “HUMAN MONKEY” 
HROUGH the courtesy of Mr. Farini, I have had a 
private interview with this curious little waif, which 
he is now exhibiting at the Royal Aquarium, Westminster, 
and for which he claims the distinction of being the long- 
sought-for “ missing link’”” between man and the Anthro- 
poid apes. Krao certainly presents some abnormal 
peculiarities, but they are scarcely of a sufficiently pro- 
nounced type to justify the claim. She is, in fact, a 
distinctly human child, apparently about seven years old, 
endowed with an average share of intelligence, and 
possessing the faculty of articulate speech. Since her 
arrival about ten weeks ago in London, she has acquired 
several English words, which she uses intelligently, and 
not merely parrot-fashion, as has been stated. Thus, on 
my suddenly producing my watch at the interview, she 
was attracted by the glitter, and cried out c’ock, c’ock, 
that is, clock, clock! This showed considerable powers 
of generalisation, accompanied by a somewhat defective 
articulation, and it appears that her phonetic system does 
not yet embrace the liquids 7 and » But in this and 
other respects her education is progressing favourably, 
and she has already so far adapted herself to civilised 
ways, that the mere threat to be sent back to her own 
people is always sufficient to suppress any symptoms of 
unruly conduct. 
Physically Krao presents several peculiar features. 
The head and low forehead are covered down to the 
bushy eyebrows with the deep black, lank, and lustreless 
hair, characteristic of the Mongoloid races. The whole 
body is also overgrown with a far less dense coating of 
soft, black hair about a quarter of an inch long, but no- 
where close enough to conceal the colour of the skin, 
which may be described as of a dark olive-brown shade. 
The nose is extremely short and low, with excessively 
broad nostrils, merging in the full, pouched cheeks, into 
which she appears to have the habit of stuffing her food, 
monkey-fashion. Like those of the anthropoids her feet 
are also prehensile, and the hands so flexible that they 
bend quite back over the wrists. Thethumb also doubles 
completely back, and of the four fingers, all the top joints 
bend at pleasure independently inwards. Prognathism 
seems to be very slightly developed, and the beautiful 
round black eyes are very large and perfectly horizontal. 
Hence the expression is on the whole far from unpleasing, 
and not nearly so ape-like as that of many Negritos, and 
especiaily of the Javanese “Ardi,’ figured by me in 
NATURE, vol. xxiii. p. 200. But it should be mentioned 
that when in a pet, Krao’s lips are said to protrude so 
far as to give her “ quite a chimpanzee look.’’ 
Apart from her history one might feel disposed to 
