8 SCIENTIFIC HOOKS PUBLISHED JBY 
Henrici’s Skeleton Strnctnres. 
8vo. Cloth. $1.50. 
SKELETON STRTJCTTJRES, especially in thoir Application to 
the building of Steel and Iron Bridges. By Olaus Hkstbici. 
With folding plates and diagrams. 
By presenting these general examinations on Skeleton Structures, with 
porticular application for Suspended Bridges, to Engineers, I venture to ex 
press the hope that they will receive these theoretical results with some confi- 
denee, even although an opportnnity is wanting to compare them with practi- 
oal resnlts. O. H. 
Useful Information for Railway Men. 
Pocket form. Morocco, gilt, $2.00. 
Compiled by W. G. Hamilton, Engineer. Sixth edition, revised 
and enlarged. 570 pages. 
“ It embodies many valuahle fonnuke and recipes useful for railway men, 
and, indeed, for almost every dass of persons in the world. The ‘ infonna- 
tion ’ comprises some valuable formulse and rules for the construction of 
boilers and engines, masonry, properties of Steel and iron, and the strength 
of materials generally.”—Bailroad Gazette, Chicago. 
The Mechanic’s Friend. 
12mo. Cloth. 300 Illustrations. $1.50. 
THE MECHANIC’S FEIEND : A Collection of Eeceipts and 
Practical Suggestions, Relating to Aquaria — Bronzing — 
Cements — Drawing — Dyes — Electricity — Gilding — Glass- 
W orking — Glues—Horology—Lacquers—Locomotives—Mag- 
netism — Metal- Working — Modelling — Pliotography—Pyro- 
techny — Railways — Solders — Steam-Engine —Telegraphy— 
Taxidermy—Varnishes— Waterproofing — and Miscellaneous 
Tools, Instruments, Machines, and Processes connected with 
the Chemical and Mechanical Arts. By William E. Axon, 
M.R.S.L.