124 
THE YOUNG SCIENTIST. 
Inquiries. 
32. Can you give me a recipe for making fusible 
metal that will melt in water? Also, how is arti- 
ficial coraling done on wood or metal? 
33. Can any of your readers tell me the propor- 
tions of sulphate of ammonia and nickel for mak- 
ing an electroplating solution? A. W. P. 
34. Please state through the columns of The 
Young Scientist, a cheap outfit for mounting in- 
sects for the microscope. Subscriber. 
35. Do you know of a dissolvent or a softener of 
printer's ink when dry? I want to take impressions 
on glass of scientific and other pictures for lantern 
slides, as many are very desirable and not in any 
catalogue of slides. C. I. S. 
36. An acquaintance of mine has a knife with his 
name eaten into the blade by some kind of acid. 
Will some one tell me what kind of acid is used for 
this purpose, and how to apply it? B. G. P. 
Answers. 
37. In answer to J. N. H. (29), Watts gives the fol- 
lowing solution for gold and silver plating without 
a battery: 1 oz. of nitrate of silver dissolved in 1 
quart of rain or distilled water. When thoroughly 
dissolved, add a few crystals of hyposulphite of 
soda, which will at first form a brown precipitate, 
but which redissolves if sufficient hyposulphite has 
been employed. The solution may be used by sim- 
ply dipping a sponge in it, and rubbing it over the 
article to be coated. A solution of gold may be 
made and used in the s me manner. W. J. A. 
EXCHANGES. 
In this column yearly subscribers who may wish 
to exchange tools, apparatus, books, or the pro- 
ducts of their skill, can state what they have to 
offer and what they want, without charge. Buying 
and selling must, of course, be carried on in the 
advertising columns. 
"A small steam engine in good order, cost $1.50, 
for a dark (bulls-eye) lantern. Geo. H. Umbach, 
139 Ross street, Brooklyn, N. Y. 
Wanted, a set of wood engraver's tools; Spencer's 
Psychology, two volumes, given in exchange; also 
other books for exchange. T. S. Price, Slack's 
Canon, Monterey Co., Cal. 
Wanted, small turning lathe about 1^ by 12 ins.; 
state what is wanted in exchange. D. Abrahams, 
195 East Broadway, New York. 
Globe microscope, magnifies 100 diameters, cost 
$2 50 to exchange for a book on shorthand, or offers. 
George R. Simpson, Jauesville, Bremer Co., Iowa. 
Wanted, back numbers of the "American Natur- 
alist*" will give "Harper's" or "Scribner's" 
monthly. Hulbert, 131 West Fifty-third street. 
New York. 
Wanted, a 5 by 8 stereoscopic camera box; Fleet- 
wood scroll saw, nearly new in exchange. L. L. 
Roberts, 1,203 Arch street, Philadelphia, Pa. 
Wanted, good microscope and Vols. I and II of 
"American Journal of Microscopy, or thorough 
works on botany; thorough instruction in short- 
band, by mail, in exchange. T. 8. Price, King's 
River, Cal. 
Wanted, in exchange for books, a second-hand 
! aquarium. Address P. 0. Box 124, Bridgeton, 
N.J. 
A collection of postage stamps for small cannon 
or small printing press; will pay difference. C. L. 
Hackett, lock box 2,210, Roanoke, Ind. 
To exchange a good magic lantern, painted 
j slides, cose $8, for a music box of same price, in 
j good order. L. D. Snook, Barrington, Yates Co., 
j N. Y. 
j McAllister's Household microscope and American 
I Agriculturist microscope, for small 5 or 6 inch turn- 
: ing lathe, or offers. J. Frank Weaver, Brooklyn, 
: Conn. 
I Graham's Handbook, Synopsis, and 1st and 2d 
j Readers Standard Phonography; tools or advanced 
scientific books preferred in exchange. E. H. Bid- 
well, Vineland, N. J. 
Complete outfit for stamping key checks, worth 
$10, in exchange for practical receipt books, or 
bracket saw with lathe and drill attachment. John 
Whitty, Jr., Polloksville, N. C. 
Woodward's Hospital Microscope wanted in ex- 
change for chemical scales and weights; difference 
in cash. J. Siler, 1,212 Broadway, St. Louis, Mo, 
For exchange, an entire printing outfit, cost $50;, 
state what you have to exchange. F. R. Miller, 
750 East Fourth street. South Boston, Mass. 
Good $50 job printing press, in perfect order, for 
a scroll and circular saw, or scroll saw alone; saw 
must be in good order. Samuel J. Jones, Box 137, 
1 Oxford, N. C. 
1 Wanted, foot power scroll saw, lathe, or both 
j combined, or good microscope, for minerals, books 
on plant culture. Art Journal in parts, or cancelled 
I postage and revenue stamps, D. S. Kimball, 48 
Exchange Place, New York. 
Wanted, small steam engine and boiler of from 
1 to 2 horse-power; state what is wanted in ex- 
change. Address Jno. McElvery, Flatbush, L. I. j 
j Wanted, telegraphic and mathematical instru- : 
[ ments; Pitman's Phonography in exchange; also, 
thorough instruction in same by mail. F. S. P., 
King's River, Fresno County, Cal. 
A set of chemicals and apparatus; also a set of 
wood engraver's tools, glass and instruction book, 
to exchange for a scroll saw and a microscope. The 
chemicals and tools cost nearly $40; will give a good 
trade. F. H. Jackson, Angelica, N. Y. 
Wanted, a copy of Holtzapfers "Mechanical 
Manipulation." State what is wanted in exchange. 
E. W., Box 4875, New York. 
Wanted, a small turning lathe in exchange for a 
pair of telephones. J. C, care Young Scientist. 
Scroll saw wanted in exchange for handsome 
portfolio of six water color sketches. Address 
F. S., care Box 4875, New York. 
Specimens of the marbles, granites and minerals 
of Vermont, in exchange for Western minerals, or 
good fossils; minerals and fossil woods from the far 
West specially desired. Dr. H. A. Cutting, State 
Geologist, Lunenburgh, Essex County, Vt. 
Wanted, complete Lester combination scroll saw- 
in good condition; books in exchange. J.T.Jack- 
son, Box 48, Metuchen, N. J. 
Gold watch (cost $150) in exchange for a good 
microscope. E. W., Box 4875, New York. 
Wanted, microscope, or scientific and mechanical 
books and apparatus, in exchange for printing 
press, cost $21, with or without type and material. 
J. P. Burbank, Salem, Mass. 
\ 
