Features
Nomenclature or Vernacular in Brick Making
Floating Soaps
The Spirograph
An Inexpensive Mercurial Air Pump
Simple Method of Measuring Heights in Hasty Topographical Surveys
The Statoscope
New Registering Barometer
Atkinson's Cycle Gas Engine
Peary'S Greenland Trip
Swing Jib Countersink Drilling Machine
Animal Life on a Coral Reef
The Breeds of Dogs
Malarial Maladies and their Geographical Extension
To Those Who Neglect Shadows
An Examination in Pharmacy
A Simple and Rapid Method of Gravimetric Analysis
Building Plans and Specifications
Patents!
Kaolin Beds
Artificial Hornblende
Useful Engineering Books
The Scientific American Supplement. Index for Vol.31
January-June, 1891.