376 
NATURE 

The reverse picture is shown in Fig. 2. 
The 
principle of dynamical similarity applies as rigidly 
to the resistance of spheres as to the surface 
friction of discs, but the experimental results vary 
very widely over almost the whole of the experi- 
An interesting contribution on the 
mental range. 
reasons for such large experimental discrepancies 
is made by Prof. Prandtl, who showed that a wire 
of small diameter put round a sphere in an appro- 
priate place had the’ somewhat surprising effect 
of reducing the resistance to about one-third of 
that of the smooth sphere. 
that a gauze screen introduced into the air current 
immediately in front of the sphere had a similar 
The conclusion appears to-be justified that 
the flow of air round a sphere is so very sensitive 
effect. 
that 
small 
06 

It was further shown 
year. 
noon. 
contact with them. 
Tirschenreuth 






Resistance des + chézes 
departures from strict geometrical | Atkinson. 
similarity and from the condition of uniform He was born at 
¢ | XMiiaele 
| | 1719 
| aK | 1st) — 1615 
lo NS 1832 
| IL \ A } 1880 
In /\ 1906 ° 
aN ALAN | : 
TNEVTA 7 Geax e ii oe | 1907-1909 
4 UW EY A | YSN e | 1312 
; yr TO \} 
Bo tr A \ VN. 1 1912 
| | ar V pee e | on 
Sacre See es , | 1912-113 
—- 1 1913-191 
relative motion are sufficient to account for the 



[JUNE 3, 1915 
DR: HUGO MULLER, F.R.S. 
HE death of Hugo Miller will -be greatly 
deplored by all who knew him—he was one 
_ of those few men who only make friends and at 
| once inspire regard in all who are brought into 
He died suddenly, at his 
country home, at Camberley, Surrey, in the early 
hours of Sunday, May 23, in his eighty-second 
Though very deeply distressed by the war, 
he enjoyed his usual good health to the last; in 
fact, he was in his garden until late in the evening 
on the previous Saturday and had worked in the 
Davy-Faraday laboratory up till Friday: after- 
He was buried at Brookwood Cemetery 
on Thursday last alongside his old friend Dr. 


Seimte 
Marit fe) 
poe ese e 
Pagerhyelaw 
EEE ES Nosy) 
Lotenino 
Reich. ee 
Mendilichf ® 
hs ® 
¥ Combes 
oumia a f 
real be ded 
Slemelberg ) 
Sheba tia ae 
Biffet iW. O (tana) 
Manraiw 
WMO, | (teassenel ) 
Siabowchinaky G.%,  (trmnel) 





100000 
large experimental variations. 
Further experiments are needed to clear up the 
position, but, obviously, no investigation can alter 
the fact that the resistance of a sphere must 
always be difficult to predict, except in very 
favourable circumstances. 
exists that the rough surface of a golf-ball has 
a very close relation to the instability of flow 
referred to, the advantage of the 
surface being so great as to render it obvious in 
the direct test on the golf links. 
It is fortunate for the future of aeronautics that 
similar troubles do not occur in connection with 
the important parts of an aeroplane, though an 
approach to such sensitivity has been found in 
the case of the fluid motion round certain struts. 
NO. 2379, VOL. 95| 

200000 
The possibility at least 

Fic. 2. 
pfalz. 
roughened 

| known 
10000 vale 100 
aN 

000 
Liebig; but he 
mineralogy 
minerals in his early days. 
Was a precocious worker, as he described the 
geognostic-mineralogical 
district in 1852 in the Regensburg Corresp. Blatt. 
| He came to this country sixty years ago, on the 
recommendation of Liebig, as assistant to Dr. 
Warren de la Rue. Their first joint work involved 
the examination of Burmese naphtha at a time 
| when very little was known of the petroleums. 
But they took up a variety of subjects and one of 
their most valuable contributions was the well- 
chloride-of-silver-zince 
which they devised. Dr. Miller also worked with 
and 



300000 
an 
features of 


600000 
He was educated as a chemist at Leipzig, 
at G6ttingen under Wohler and at Munich under 
also took special 
ardent 
It is clear that he 
interest 
collector 
his 
constant battery 
in the Ober- 
home 
