Vol. XXV. No. 5.] 
POPULAR SCIENCE I^EWS. 
67 
the world — without arms ! He was an exceedingly 
bright child, of sunny temperament, loved by all 
Ijccause of his amiable disposition. From early 
boyhood he evinced a decided passion for drawing. 
His great preference for the cultivation of this 
talent was, however, strongly discountenanced by 
his tutors, who encouraged a closer application to 
the routine curriculum of school work. 
Nature having deprived him of the use of arms, 
necessity cultivated his feet to supply the defi- 
ciency. Indeed, these members acquired an almost 
incredible degree of perfection in serving hira as 
hands. The knee and ankle are remarkably supple 
and limber. His feet possess rare delicacy of 
touch. His fineness of execution in wielding the 
l)rush would be considered a remarkable gift when 
centered in tlie liands. That his feet should be 
endowed witli this artistic power of conception is 
almost miraculous. They accomplish witli ease 
tlie most difficult demands of his vocation — that 
of an artist. He received pl-ivate drawing lessons 
until 1871, when he became pupil under Professor 
Roeting of the Dusseldorf Academy of Painting. 
His first effort in oil was a feminine portrait. It 
l)ore the stamp of his remarkable genius and soon 
(•stat)lished his reputation as an artist. 
It is interesting to observe Slepen at work. He 
draws free foot, and paints, seated upon a low 
ottoman. Another abnormal deviation is the fact 
that he is left-footed, painting exclusively with 
liis left foot. He is quite independent in his 
mechanical work, and declines all aid that can be 
dispensed with. He mixes his own colors, screws 
iind unscrews his-tubes, etc. The only assistance 
he asks of the servant in constant attendance, is 
the proper adjustment of his easel. 
The general public usually sees Siepen in a low 
carriage. This has created the impression that his 
feet are unfit to serve him in llicir normal capacity. 
( )n tlie contrary, he is a graceful and rapid pedes- 
triau. He rides only, to better preserve the ability 
of liis feet for their, to him, more important 
mission. Obviously, overtaxing the strength of 
these members in walking, renders them noticably 
less pliant. The artist is now in his 40th year. 
He enjoys, perfect health, is active and ambitious. 
.Vbove all is he anxious to have his productions 
prized from a purely artistic standpoint. That 
they shall be judged entirely upon their merits as 
works of art, regardless of the slightest consider- 
ation for their marvelous means of execution. He 
did all in his power to conceal liis wonderful mode 
of workmanship, fearing his paintings would find 
admirers and purchasers, merely because of this 
unique peculiarity. His subject, " llie Two Sis- 
ters," assured his fame, ere the deficiency in his 
physical development wa.s known to the public. 
Consequently his cherished wish was happily ful- 
filled. 
•♦» 
A Xew Chemical.— The champion «ord thus 
far coined, looking at it longitudinally or horizon- 
tally, is doubtless quinolineparamethenylbenzenyl- 
a/.oximeparacarboxylic acid. .Most lexicographers 
will be afraid to tackle it in its entirety. Nick- 
names should be allowable in chemical and phar- 
maceutical nomenclature for such mastodonic 
monstrosities. 
A CONVENIENT MET'HOD FOR DETECT- 
ING AND ESTIMATING PETROLEUM IN 
SPIRITS OF TURPENTINE. 
BY SAMUEL J. HINSDALE. 
Put ten drops of the spirits to be examined in a 
moderately concave watch glass, and float the 
glass on about a quart of water which has a tem- 
perature of about 170° F. If the spirit is pure it 
will evaporate and leave tlie glass quite dry in 
seven minutes. If the spirits contains even five 
per cent, of petroleum it will not have completely 
evaporated in that time. This experiment will 
prove the absence or presence of petroleum in the 
sample. 
To estimate the percentage of petroleum adul- 
teration, weigh a watch glass and put into it ten 
drops of the mixture and weigh again. Put into 
another glass ten drops of pure spirits of turpen- 
tine, and float both glasses on about a quart of 
water at about 170° F. As soon as the pure spir- 
its has evaporated, take oft' the glass which con- 
tained the mixture and weigh it. The difference 
between this weighing and the weight of the 
glass will indicate about four-fifths of the amount 
of petroleum in the mixture. Knowing the 
weight of the ten drops the percentage can be 
calculated. 
A bent loop of wire is convenient to place on 
and remove the watch glass from the water. ITie 
hydrometer will detect adulteration with benzine 
or petroleum, but it cannot be used to estimate 
the amount of adulteration. The specific gravity 
of pure spirits of turpentine is about 0.865 at 60° 
F. Petroleum is the usual adulterant. 
[Original In Populak Science News.] 
AN EXPERIMENT FOR SHOWING DIFFU- 
SION OF LIQUIDS. 
BV M. W. EWIN. 
On Friday, .' ]) il 18, 1890, I made the following 
experiment foi- a class in physics. I filled a half 
pint quinine jar with blue litmus water, and ap- 
plying a piece of paper to the mouth (as in exper- 
iment showing upward pressure of atmosphere) 
inverted it over a quart fruit jar filled with slightly 
acidulated water. In slipping the paper out a 
very small quantity — perhaps two tablespoon- 
f uls — of the litmus water was lost. When finally 
in position the moutli of the genuine jar was cov- 
ered by the acidulated water while its neck rested 
upon the mouth of the fruit jar. For some days 
tlie litmus water (except that in tlie neck) re- 
mained unchanged in color. On Monday, April 
28, several days, however, intervening without 
inspection, the color had changed to red. I^eav- 
ing the bottles in the same position some weeks 
longer the water of the upper bottle became al- 
most colorless, while tliat of the lower had under- 
gone no perceptible change. 
Reno, Nevada. 
*♦+ 
PREVENTION SOCIETIES. 
Societies for the prevention of one thing or 
another are a nuisance. They may do some good, 
but they do it in the wrong way. It is idiotic, it 
is impertinent, it is unbearable, to have some soci- 
ety or person constantly at our elbows trying to 
compel us to do what they wish us to do. Men 
who are cruel to animals are very hateful persons, 
but they are not nearly as ol)noxious as men who 
make a profession of meddling with other people's 
atfairs and compelling them to do what they do 
not wish to do. Physical interference with per- 
sonal liberty is the greatest possible offense that 
one man can commit against another. Each per- 
son should be allowed to commit as many blunders 
as he likes, so long as he does not interfere with 
the person, property, or actions of another. When 
this liberty is not accorded, the whole universe is 
thrown out of gear, and friction and misery ensue. 
— Exdhange. 
<♦► 
SCIENTIFIC BREVITIES. 
Lightning. — It has been calculated that the 
electromotive force of a bolt of lightning is about 
3,.500,000 volts, tlie current about 14,000,000 am- 
peres, and the time to be about 1-20,000 part of a 
second. In such a bolt there is an energy of 
2,4.50,000,000 watts, or 3,284,182 h. p. 
It is reported that the observers at Mount Hamil- 
ton have lately kept a sharp eye turned upon the 
shadow of one of the moons of the planet Jupiter. 
Tliis shadow seemed double, indicating that the 
tiny moon which cast it is also double. Since the 
first hint of the discovery many observations have 
tieen made tlirough the IJck glass, all tending to 
confirm the original impression, to wit : That this 
particular satellite of the greatest of the planets 
is double — a dot of a moon revolving around the 
main moon. 
Abhasion of Gold Coin.— By careful experi- 
ments made at the United States Mint, says The 
Iron Industry Gazette, it has been shown that $5 
are lost by abrasion every time §1,000,000 in gold 
coin are handled. Tlie experiments were conducted 
with biigs containing .f ,5,000 each, and it was shown 
that the mere lifting of tlie 200 bags making up 
■SI ,000,000 to a truck to be removed to another 
vault, resulted in the loss stated, and that their 
transfer from the truck again made a second 
similar loss. 
The Highest Inhabited Places. — Tlie highest 
place in the world regularly inhabited is stated to 
be the Buddhist monastery, Ilalne, in Thibet, 
whiph is about 16,000 feet above sea level. The 
next highest is Galera, a railway station in Peru, 
which is located at a Iieight of 15,63.5 feet. Near 
it, at the same level, a railway tunnel 3,847 feet in 
lengtii is being driven through tlie mountains. 
The elevation of the city of Potosi, in Bolivia, is 
13,3.30 feet; Cuzco, Peru, 11,.380 feet; La Paz, 
Bolivia, 10,883 feet, and Leadville, Colo., 10,200 
feet. 
A Novel ]/,aw Suit recently came before the 
court of Petersburg, Virginia. A short statement 
of the facts is as follows : Davis, a pliotographer, 
some time ago sold to a florist a lot of refused 
negatives, which he wanted to use to cover his 
hot-house. Foster, a rival photographer, bought 
some four hundred of the negatives from the 
florist, and from these printed photographs and 
exposed them as specimens in his gallery. Davis 
obtained an injunction to prevent Foster from so 
using the negatives, and the court perpetuated the 
injunction. 
The Woulij's Population in 1890.— In the 
proceedings of the Royal Geographical Society 
for January, 1891, it is estimated that tlie popula- 
tion of the world in 1890 was 1,487,600,000, repre- 
senting an average of 31 to the square mile and an 
increase of 8 per cent, during the decade. Of the 
continents, Asia has the largest population, 
850,000,000, and the lowest percentage of increase, 
6 per cent. Australasia has the smallest popula- 
tion, 4,730,000, and the smallest average per square 
mile, 1.4, but tlie highest rate of increase during 
the decade, 30 per cent. Europe is the most thickly 
settled continent, with a population of 380,200,000, 
which is 101 to the square mile. The population 
of North America is estimated at 89,250,000, which 
is an average of 14 to the square mile, and repre- 
sents an increase of 20 per cent, during the past 
decade. 
