vill 
Noteworthy Articles 
ON TIMELY TOPICS 
SEWAGE AND ITS DISPOSAL. A 
review of modern methods. By H. 
Lemmoin-Cannon. Scientific American 
Supplement 1551. 
ELECTRIC LIGHTING FOR AMA- 
TEURS. How a small and simple ex- 
perimental installation can be set up 
at home. Scientific American Supple- 
ment I551. 
CHEMICAL AFFINITY. Simply ex- 
plained by Sir Oliver Lodge. Scienti- 
fic American Supplement 1547. 
CASE-HARDENING. By 
Flather. 
David 
Scientific American Supple- 
ment 1547. 
ELECTRIC IGNITION SYSTEMS. A 
comprehensive article by E. W. Rob- 
erts. Scientific American Supplement 
1546. 
CONCRETE. A general article on its 
merits and defects. Scientific Ameri- 
can Supplement 1543. 
REINFORCED CONCRETE. Some of 
its Principles and Applications with 
practical Illustrations. Scientific 
American Supplements 1547, 1548, 
1551. 
ELECTRONS AND THE ELECTRO- 
NIC THEORY are discussed by Sir 
Oliver Lodge in Scientific American 
Supplements 1428, 1429, 1430, 1431, 
1432, 1433, 1434. 
WIRELESS TELEGRAPHY. Its Pro- 
gress and Present Condition are well 
discussed in Scientific American Sup- 
plements 1425, 1426, 1427, 1386, 1388, 
1389, 1383, 1381, 1327, 1328, 1329, 1431. 
HOW TO CONSTRUCT AN EFFI- 
CIENT WIRELESS TELEGRAPH 
APPARATUS AT SMALL COST is 
told in Scientific American Supplement 
1363. 
SELENIUM AND ITS REMARK- 
ABLE PROPERTIES are fully de- 
scribed in Scientific American Supple- 
ment 1430. The paper is illustrated by 
Numerous engravings. 
LANGLEY’S AERODROME. Fully de- 
scribed and illustrated in Scientific 
American Supplements 1404, 1405 and 
1546. 
STEAM TURBINES. Their Construc- 
tion, Operation and Commercial Ap- 
plication. Scientific American Supple- 
ments 1306, 1307, 1308, 1422, 1400, 1447, 
1370, 1372, 1521. The articles have all 
been prepared by experts in steam en- 
gineering. 
PORTLAND CEMENT MAKING is 
described in excellent articles con- 
tained in Scientific American Supple- 
ments 1433, 1465, 1466, 1510, I5II. 
THE TANTALUM LAMP. A full illus- 
trated description of a lamp having a 
metallic filament and burning at once 
without preliminary heating appears in 
Scientific American Supplement 1523. 
THE WATERPROOFING OF 
FABRICS is thoroughly discussed in 
Scientific American Supplement 1522 
by an expert. 
THE SPARK COIL, ITS CONSTRUC- 
TION AND MAINTENANCE, is the 
subject of a painstaking article in 
Scientific American Supplement 1522. 
ELECTRIC IGNITERS FOR GAS EN- 
GINES are discussed in Scientific 
American Supplement 1514. 
CARBURETERS, a subject of immense 
importance to automobilists and the 
users of oil engines, is well treated in 
Scientific American Supplement 1508. 
EPICYCLIC TRAINS, which play an 
important part in toothed gearing, are 
ably described in Scientific American 
Supplement 1524. 
Each number of the Scientific American 
Supplement costs 10 cents by mail 
Send for to10 Supplement Catalogue 
FREE to any address 
MUNN & COMPANY 
361 Broadway New York 
AMERICAN HOMES AND GARDENS 
PICTURE-FRAMING OUTFIT 
HE Handy Man’s Workshop is not 
complete without a picture-framing 
outfit. A device for holding the 
molding while nailing and gluing which is 
practical can be easily made as follows: 
The clamps can be secured from the tops 
of two old clothes wringers by sawing 
about three inches on either side of the 
screw. The base of the device should be a 
2-inch hardwood plank, or better still, two 
pieces of inch board glued together with the 
grain of one running at right angles with 
that of the other. The size of the base 
ought to be 18 by 22 inches. A board 6 
by 8 and % inch thick should be glued and 
screwed to the base, which can be readily 
done. Bolt the clamps to the base as 
illustrated, leaving sufficient space between 
the ends of the screws and the holding 
board to place the widest molding which 
one would use for any frame. This space 
must not be too wide, for the screw has a 
tendency to spring up when heavy pressure 
is applied. Small blocks are to be used 
when narrow molding is being held, or on 
any molding which the end of the screw 
would dent. The difficulty in making 
frames is in holding the pieces firmly to- 
gether while nailing. 
BUILDING MATERIALS AND NOISE 
GERMAN - scientist named Nuss- 
baum has for a long time been study- 
ing the question of the suppression 
of noise in dwelling houses. He has ex- 
perimented both in the laboratory and in 
private houses. One point he has ascer- 
tained is that the more solid and tough and 
strong the building material is the more 
quickly and loudly it conveys sound, and 
its conductivity can best be tested by strokes 
with a piece of metal. The higher the tone 
the greater the conductivity. 
Nussbaum has made many experiments 
with partition walls. He has found that those 
of tiles and cement transmit sound most 
and those of solid clay least. Between the 
two comes the wall of ordinary brick, and 
the more the brick is burned the more noise 
it transmits. A quickly hardening lime 
mortar is to be preferred to a clay mortar. 
One experiment showed that when a floor 
was covered with sand and cork mats 
spread over it hardly any noise penetrated 
to the room below, but that when the cork 
mats were joined together by any material 
underneath, noises were at once perceptible. 
To the question, how are the sounds of 
the piano or the violin in the neighboring 
apartments to be excluded? Nussbaum 
has returned the suggestion that the ceil- 
ings be treated as he successfully treated 
his telephone cell. namely, to line them with 
a layer of zinc or lead. 
DAHLIAS AND POTATOES 
Y a kind of horticultural irony the 
B dahlia, that popular flower that so often 
forms a conspicuous display at flower 
shows, has a dreadfully prosaic parentage. 
It has developed from the Mexican tubers 
introduced about one houndred and twenty 
years ago by the Swedish naturalist, Dr, 
Dahl, for the purely commercial purpose 
of supplementing the potato! The doctor’s 
scheme did not meet with favor, and the 
dahlia dish soon disappeared from British 
tables, but the gardeners of the old country 
at once perceived the great potentialities of 
the flower, and accordingly proceeded to 
produce the double dahlia and other de- 
lightful floral fantasies. 
August, 191! 
ottage 
Designs 
HESE books offer to architects, builders, 
homeseekers and investors by far the 
most complete collection of plans ever 
brought out, while the price is so low as to 
place them within the reach of all who have 
an interest in the building of homes. The 
designs are compiled with a view to represent- 
ing all grades oi cost, from the simplest types 
of cottages, as illustrated in the first series, to 
the comparatively elaborate structures reaching 
to $10,000 or more, in cost, treated in the 
fourth series, so that examples are given cever- 
ing nearly every requirement, with respect to 
cost, in inexpensive homes. 
No. 1. Cottage Designs 
with Constructive Details 
A series of twenty-five designs of cottages, 
most of which have been erected, ranging in 
cost from $600 to $1,500; together with details 
of interior and exterior finish, all drawn to 
convenient scale, and accompanied by brief 
specifications. Illustrated with 538 full-page 
plates of floor plans, elevations and details. 
r) 
No. 2. Low Cost Houses 
with Constructive Details 
Embracing upward of twenty-five selected 
designs of cottages originally costing from 
$1,000 to $3,000, accompanied with elevations, 
floor plans and details of construction, all drawn 
to scale, together with brief descriptions and, 
in many instances, full specifications and 
detailed estimates of cost. Illustrated by 61 
full-page plates of floor plans, elevations and 
details. 
No. 3. Modern Dwellings 
with Constructive Details 
A selection of twenty designs of artistic 
suburban dwellings erected in various parts of 
the country, at costs ranging from $2,800 
to $7,000; embracing floor plans, elevations 
and constructive details, showing interior and 
exterior finish, and drawn to scale, together 
w.th extracts from the specifications. Illus- 
trated by means of half-tone reproductions, 
from photographs of the completed structures, 
and 61 full-page plates, of floor plans, eleva- 
tions and details. 
No. 4. Suburban Homes 
with Constructive Details 
Comprising twenty selected designs of attrac- 
tive suburban homes, ranging in cost from 
about $3,000 upward ; embracing floor plans, 
elevations and constructive details, showing 
interior and exterior finish, a!l drawn to scale, 
together with extracts from the specifications. 
Illustrated by means of half-tone reproductions 
from photographs of the completed structures, 
and 75 full-page plates of plans, elevations 
and details. 
One Dollar Each, Postpaid 
(SOLD SEPARATELY) 
MUNN & CO. 
Publishers of Scientific American 
361 Broadway, New York 
