136 
THE YOUNG SCIENTIST. 
EXCHANGES. 
Send to W, S. Beekman, 2 Fountain PL, Roxbury, 
Mass., for minerals and chemicals ; state what you 
have for exchange; books, mieros(}opes, chemi- 
cals and electrical apparatus wanted. 
What offers for Household microscope, darning 
machine, new 7 shot revolver and box of car- 
tridges, small gold watch, violin and case. J. H. 
Bell, Tarboro, Edgecombe Co., N. C, 
A magic lantern with eight slides, original price 
$6, to exchange for a gun, telescope, good fishing 
rod, or revolver. J ohn H. Boies, Box 246, Hudson, 
Mich. 
Wanted, scientific books and instruments ; 
please send list and what you want for them. W. 
A. Brooks, Jr., P. O. Box 122, Salem, Mass. 
To exchange, a seven shot Smith & Wesson 
revolver, 22-100 calibre, in good condition ; state 
what is offered in exchange. W. B, Flausburgh, 
Xia Fargeville, N. Y, 
For anything relating to drawing or penman- 
ship, will exchange a new book on fortute telling, 
and a treatise on chiromancy ; 1,750 engravings ; 
price $2. W. C. Gamble, Bothwell, Ontario, Canada. 
To exchange, a house swing, cost $3, in good 
order, for a hammock. Henry M. Haviland, 103 
Park PI., Brooklyn, N. Y. 
Wanted, a magic lantern good enough for public 
exhibition ; state what is wanted in exchange. 
G. W. Kessler, Altoona, Pa. 
To exchange, a collection of about 125 rare 
minerals, each encased in uniform box, accurately 
labeled, classified and numbered, for telegraph 
sounder, battery, &c., complete, model engine, 
microscope or offers. Jos. G. Kitchell, 345 Kace St., 
Cincinnati, O. 
A horizontal slide valve steam engine and tubu- 
lar boiler, cylinder l>4x2>3in., with pump and 
heater all complete, ready to set up and run ; 
worth $25; for type and accessories for job print- 
ing, or offers. Geo. L. Lamson, La Fargeville, N. Y. 
Wanted, good nickle rim banjo ; have barber 
chair to give in exchange. C. H Lockwood, South 
Westerlo, Albany Co., New York. 
Wanted, works ou natural sciences, phrenology, 
or physiology, loose or bound numbers of month- 
lies on science or health, etc., small printing press 
or microscope ; for books or lessons in shorthand. 
H. C. Lucas, Macomb, 111. 
A good philosophy, 393 pp., will exchange for 
"American Agriculturist," microscope or book on 
microscopy. J. Y. Mohler, Middlesex, Cumb. 
€o.. Pa. 
A rifle (range 60 rods), gold watch and violin; 
your choice ; a galvanic battery preferred in ex- 
change. Jas. M. Ovenshire, Barrington, N. Y. 
Wanted, to exchange all the numbers of " The 
Oincinnati Artisan," for the year 1879, and three 
l)eautiful scroll saw designs, for a small but good 
dark lantern (bull's eye). E. E. Pinkerton, Afton, 
Union Co., Iowa. 
To exchange for other things, one hundred theo- 
logical (evangelical) and miscellaneous books. E. 
J. Rich, Brookfield, Mass. 
Wanted, a floor-board planer in exchange for 
scientific books, microscope or micro-spectro- 
scope, etc. Henry A. Sprague, Charlotte, Maine. 
Wanted, to exchange two telephones, a B-flat 
cornet, an aquarium with fountain attachments, 
for a pair of telegraphs and keys. W. C. Vick, 
East Ave,. Rochester, N. Y. 
For exchange, two Excelsior, No. 2, printing 
presses ; state offers. W. A. Wilcox, Tunkhan- 
nock. Pa, 
A book, " Fret Sawing for Pleasure and Profit," 
by H. T. Williams, cost 50 cts., in exchange for a 
book of sawing patterns, or offers of similar value. 
S.B. Wilson. Lenoir, N. C. 
PUBLISHER'S DEPARTMENT. 
steel Pens.— A pen, in the course of manu- 
facture, goes through twenty-five different pro- 
cesses, takes four weeks to complete, and yet is 
offered to the general public by the gross box at 
considerably less than a cent a pen. It is only by 
manufacturing pens on so large a scale that they 
can be produced at prices to meet the demands of 
competition, and it is only by producing articles 
of unexceptionable quality that such quantities 
can be disposed of. The largest manufacturers 
in the United States are the Esterbrook Steel Pen 
Company, of Camden, N. J., their warehouse 
being at 26 John street, New York. Their pens 
are for sale by all the leading stationers in the 
country. 
Object Lessons for Old and Young".— The 
infiuence for good which the Exhibitions of the 
American Institute have exerted upon the young 
people of New York and neighboring cities, can 
scarcely be overestimated. Year after year it 
furnishes to old and young a series of object 
lessons unequalled in extent and character. Not 
only do we find a most extensive collection of in- 
teresting products, the newest and best of their 
kind, but we are enabled to see in many cases the 
actual process of their production ; and this, to 
many young people, is a sight which cannot 
easily be found elsewhere, for it is only the 
privileged few who have the entree to factories, 
workshops and laboratories. We know of no 
place where our young readers can spend a few 
hours to greater advantage than in the exhibition 
of the American Institute. 
The House-bell of the Future.— When the 
modern house-bell, with its meandering wires 
leading through the most crooked by-paths from 
mistress to servant, was first substituted for the 
primitive clapping of hands which is still in vogue 
in the East, what a wonderful improvement it 
must have appeared! But even the house-bell 
has its defects, the most obvious and prominent 
of which is that it cannot serve to convey a -mes- 
sage, but merely to summon the messenger. 
When, therefore, the telephone was invented, it 
became obvious that this must speedily displace 
all wire bells, for here we have the means of im- 
parting a message without the necessity of first 
calling the servant to us. Half the time and 
trouble is therefore saved, and as the wires for 
the telephone can be put up along any wall, and 
may be twisted and turned round any corner, the 
great trouble and annoyance attending the putting 
up of bell-wires and cranks, with the accompany- 
ing nuisance of having to bore through partitions, 
is done away with. The expense of the telephone 
was at first almost prohibitory, but they are now 
manufactured and sold by such firms as Kent. 
Woodstock & Co., 25 Congress St., Boston, at such 
a low rate that any one may have them. The 
telephone, therefore, may safely be called the 
house-bell of the future. 
