l Hatter.
Illustrated by Drawings of Machinery, etc. 8vo. $1.25

$HENRY.--The Early and Later History of Petroleum$:

With Authentic Facts in regard to its Development in Western
Pennsylvania. With Sketches of the Pioneer and Prominent Operators,
together with the Refining Capacity of the United States. By J.T.
HENRY. Illustrated 8vo.

$HOFFER.--A Practical Treatise on Caoutchouc and Gutta Percha$,

Comprising the Properties of the Raw Materials, and the manner of
Mixing and Working them; with the Fabrication of Vulcanized and
Hard Rubbers, Caoutchouc and Gutta Percha Compositions,
Water-proof

Substances, Elastic Tissues, the Utilization of Waste, etc., etc.
From the German of RAIMUND HOFFER. By W.T. BRANNT. Illustrated
12mo. $2.50

$HOFMANN.--A Practical Treatise on the Manufacture of Paper in all
its Branches$:

By CARL HOFMANN, Late Superintendent of Paper-Mills in Germany and
the United States; recently Manager of the "Public Ledger" Paper
Mills, near Elkton, Maryland. Illustrated by 110 wood engravings,
and five large Folding Plates. 4to., cloth; about 400 pages. $50.00

$HUGHES.--American Miller and Millwright's Assistant$:

By WILLIAM CARTER HUGHES. 12mo. $1.50

$HULME.--Worked Examination Questions in Plane Geometrical
Drawing$:

For the Use of Candidates for the Royal Military Academy, Woolwich;
the Royal Military College, Sandhurst; the Indian Civil Engineering
College, Cooper's Hill; Indian Public Works and Telegraph
Departments; Royal Marine Light Infantry; the Oxford and Cambridge
Local Examinations, etc. By F. EDWARD HULME, F.L.S., F.S.A.,
Art-Master Marlborough College. Illustrated by 300 examples. Small
quarto. $3.75

$JERVIS.--Railroad Property$:

A Treatise on the Construction and Management of Railways; designed
to afford useful knowledge, in the popular style, to the holders of
this class of property; as well as Railway Managers, Officers, and
Agents. By JOHN B. JERVIS, late Civil Engineer of the Hudson River
Railroad, Croton Aqueduct, etc. 12mo., cloth $2.00

$KEENE.--A Hand-Book of Practical Gauging$:

For the Use of Beginners, to which is added a Chapter on
Distillation, describing the process in operation at the
Custom-House for ascertaining the Strength of Wines. By JAMES B.
KEENE, of H.M. Customs. 8vo. $1.25

$KELLEY.--Speeches, Addresses, and Letters on Industrial and
Financial Questions$:

By HON. WILLIAM D. KELLEY, M.C. 544 pages, 8vo. $3.00

$KELLOGG.--A New Mone