iv AMERICAN HOMES AND GARDENS 
August, 1912 
THE ROTARY 
STEAM ENGINE 
HE Rotary Steam Engine has 
attracted the best thoughts of 
inventors and students for many 
years. All interested should read 
carefully the very complete in- 
formation found in the files of the 
Scientific American Supplement. 
Every class and type of rotary 
engines and pumps is described 
and illustrated. 
Scientific American Supplement 470 describes 
the Harrington Rotary Engine, a form of intermit- 
tent gear. 
Scientific American Supplement 497 describes 
Fielding & Platt’s Universal-joint Rotary Engine. 
Scientific American Supplement 507 describes 
the Jacomy Engine, a square-piston type. 
Scientific American Supplement 528 describes 
Inclined-shaft Rotary Engine, using the universal- 
joint principle. 
Scientific American Supplement 558 describes 
the Kingdon Engine, a “‘wabble-disk”’ design. 
Scientific American Supplement 636 describes 
Riggs’ Revolving-cylinder Engine, suggesting the 
present Gnome motor. 
Scientific American Supplement 775 describes 
Revolving-cylinder engines of several forms. 
1109-1110- 
1111 contains a series of great interest, describing 
Scientific American Supplement 
and illustrating all the principal types of rotary en- 
gines and pumps. This set should be studied by 
every inventor and designer. 
Scientific American Supplement 1112 describes 
the Filtz Rotary Motor, using helical surfaces. 
Scientific American Supplement 1158 describes 
Hult’s Rotary Engine, an eccentric-ring type. 
Scientific American Supplement 1193 describes 
Arbel & Tihon'’s Rotary Motor, an ingenious 
eccentric type, now on the market as a pump. 
Scientific American Supplement 1309 describes 
The Colwell Rotary Engine, in which a piston 
travels entirely around an annular cylinder. 
Scientific American Supplement 1524 describes 
Rotary Engine on the intermittent-gear principle. 
Scientific American Supplement 1534 contains 
a valuable column on the difficulties of rotary en- 
gine design. 
Scientific American Supplement 1821 contains 
an article describing many new forms of rotary 
engines of the most modern design. 
Scientific American, No. 23, Vol. 102 contains a 
full description of the recent Herrick Rotary En- 
gine, an eccentric type with swinging abutment. 
Scientific American, No. 23, Vol. 104 describes 
Jarman’s Engine, on the sliding-valve principle. 
Scientific American, No. 14, Vol. 106 describes 
the Augustine Rotary Engine, with novel features 
incorporated in the sliding-valve design. 
Each number of the Scientific American or 
A set of 
papers containing all the articles here men- 
tioned will be mailed for $2.00. They give 
more complete information on the subject 
Send 
for a copy of the 1910 Supplement Catalogue, 
the Supplement costs 10 cents. 
than a library of engineering works. 
free to any address. Order from your news- 
dealer, or the publishers. 
MUNN & CO., INC. 
361 BROADWAY, _N. Y. CITY 
the temperature in the various ovens 
ranged anywhere from 57 to 98 degrees. 
This upsets our theory. 
“T asked the Arab what per cent. of the 
eggs hatched out, and he immediately 
asked me the same question. I replied that 
sometimes it was 30 to 40 per cent. and 
sometimes it was 70 to 80 per cent., where- 
upon the Arab laughed and said that with 
him it was never less than 90 per cent. ; oth- 
erwise he would starve. He then explained 
that he hatched for forty neighbors for 
five months in the year, beginning in Janu- 
ary, getting 6,000 eggs from each. He is 
paid $5 for his work by each of his cus- 
tomers. 
EGGS IN EGYPT 
HE hatching of eggs by means of arti- 
ficial heat has been practiced in China 
and in Egypt from prehistoric times. In 
the latter country there still exist ancient 
egg-hatcheries or “mamals” that have been 
in continuous use in the same family for 
many generations. These incubators con- 
sist of large brick ovens that will hold about 
thirty to sixty thousand eggs at a time. The 
fire is built inside the oven and is watched 
carefully for ten days, after which no addi- 
tional heat is necessary. The method of 
building the fires and maintaining them so 
as to preserve the right temperature are 
trade secrets that are jealously guarded 
and usually kept in the family. About 
sixty-five to seventy per cent of the eggs 
are said to be successfully hatched by these 
methods. The production of eggs for the 
export trade has come to be a very import- 
ant industry of Egypt. During the Winter 
of 1911-1912 the export amounted to 
83,608,000 eggs, having a value of 
$627,000. That is at the rate of about 
nine cents a dozen. Compared to the prices 
paid in this country last Winter, it would 
almost seem that it might pay to bring eggs 
to New York from Cairo. Most of the 
Egyptian eggs go to England; last year 
74,000,000, or nearly ninety per cent, were 
sent there. France had over 3,000,000, and 
the rest were divided among a number of 
countries. The eggs shipped from Egypt 
are generally smaller than those we are ac- 
customed to; but when we consider the 
amount of food material contained in them, 
even these small eggs are very cheap when 
compared with prices in. this country or 
in Europe. 
UNUSUAL OCCUPATIONS 
HEN the thirteenth census is com- 
pleted, that is when the last compila- 
tion has been made and each individual has 
been put in the proper class, it will be the 
most exhaustive classification ever made 
by the Census Bureau. For instance, while 
machinists will of course be placed under 
one general heading, each of them will be 
classified according to the particular work 
he is doing, and so with other trades and 
industries. Some of the sub-classes will 
contain but a single name. This will bring 
to light a number of queer ways in which 
some people are engaged in earning a liveli- 
hood. As far as the work has progressed, 
there is only one man classed as ‘‘snake 
merchant.” This man has a snake ranch in 
Texas, and has for more than seven years 
made a business of handling snakes. Dur- 
ing the year 1910 he sold over 150,000 
rattlesnakes and blacksnakes, the prices 
ranging from twenty-five cents to two dol- 
lars each. They are sold to zoos, side shows 
of circuses, medical colleges and scientists. 
Under the shoe industry one would 
hardly expect to find persons sub-classed 
judgers, fakers, plowers, sluggers, busters- 
out, cripple chasers and pancake makers, 
but there they are. Another man who will 
be all in a class by himself when the work 
is finished is a resident of Kansas City. 
His sole business is to bottle smoke of 
burning hickory logs. He claims that when 
this smoke is let loose in an airtight com- 
partment where meat has been hung it 
will produce the same results upon the 
meat as though it had been smoked in an 
old-fashioned smoke house. Such titles as 
“whittler,” in a straw hat factory; “tobles,” 
a maker of stogies; “dock walloper,” a 
longshoreman; “pouncer” in a hat-making 
establishment; ‘“‘vibrator” in a clock fac- 
tory; “tonger” in connection with oysters; 
“teaser” in a glass factory, are some of the 
other queer designations used by the Cen- 
sus Bureau. 
Indeed, there are as many women as 
there are men who pursue odd ways of 
earning money, one class of which would 
be designated as “goats,” were a common 
expression of the times used, for it is their 
business to be “discharged” from the de- 
partment stores in which they are “em- 
ployed” a number of times each day, or 
as often as necessity might demand. When 
a grouchy or haughty customer makes com- 
plaint of discourteous treatment, or what 
not, against a clerk, one of the “goats” is 
summoned to the office as the person in 
charge of that particular department. 
There she is given a good talking to before 
the angry customer and summarily dis- 
missed, and the complainant goes away re- 
joicing. 
Women policemen are becoming rather 
commonplace. We have a woman chief of 
police in Kansas; a town in Pennsylvania 
boasts a fair deputy sheriff, who is a college 
graduate, and Los Angeles was the first 
city to appoint a woman to its police force. 
One woman in Pennsylvania earns her 
daily bread by raising Persian cats and 
selling them for from twenty-five to one 
hundred dollars each. She not infrequently 
makes large sales to wealthy cat fanciers. 
Still another woman in Maryland devotes 
her time to pigeon raising, claiming her in- 
come from the industry to be about $700 
a year. 
One of the most unique trades of the 
entire list, however, is that carried on by 
a man in Seattle. His business, and a 
profitable one, too, is to secure the mus- 
taches from walrus killed in Bering Straits 
and sell them to the Chinese for toothpicks. 
These stout bristles are plucked from the 
nose of the walrus by Indians, tied into 
small bundles and sold by him on the 
Pacific Coast to agents who ship them to 
China, where they are in great demand. 
In an aged bull walrus the bristles are 
about a foot long and nearly as thick as 
a lead pencil. Besides being extremely 
tough, they can, when made into picks, be 
pushed between the teeth without injury 
to the enamel. Last year this dealer cleared 
something like a thousand dollars by his 
traffic in walrus whiskers. 
A NEW GERMAN AEROLOGICAL 
STATION 
GC ERMANY, which already possesses a 
far greater number of institutions for 
the exploration of the upper air than any 
other country, is to have a new one, at 
Rostock. That city has given the neces- 
sary land, on which the station will be in- 
stalled by Capt. Hildebrandt, of Berlin, and 
Prof. Ktmmell, of Rostock. Besides the 
usual observations with meteorological kites 
and balloons, measurements of atmospheric 
electricity and radioactivity will be made, 
