There are also a number of appliances used mostly in experimental and educational work. Such, for instance, are Electrical or Electrostatic Machine (Vol. 9, p. 176), with many illustrations; Electrophorus (Vol. 9, p. 237), and Leyden Jar (Vol. 16, p. 528).
The metals, chemicals and other materials sold by dealers in electrical supplies, and their properties and uses, are described in Copper (Vol. 7, p. 102), Zinc (Vol. 28, p. 981), Lead (Vol. 16, p. 314), Sulphuric Acid (Vol. 26, p. 65), Sodium, Compounds (Vol. 25, p. 341); Chromium (Vol. 6, p. 296); Nitrogen, Compounds (Vol. 19, p. 715); Sal Ammoniac (Vol. 24, p. 59), Bichromates and Chromates (Vol. 3, p. 912), Carbon (Vol. 5, p. 305), Rubber (Vol. 23, p. 795), and Gutta Percha (Vol. 12, p. 743).
The following is a partial list, in alphabetical order, of articles of peculiar interest to dealers in electrical supplies.
- Accumulator
- Amperemeter, or Ammeter
- Armature
- Battery
- Bell
- Bichromates and Chromates
- Carbon
- Chromium
- Condenser
- Conductor, Electric
- Copper
- Dielectric
- Dynamo
- Electricity
- Electrical, or Electrostatic, Machine
- Electricity Supply
- Electrokinetics
- Electrolysis
- Electromagnetism
- Electrometer
- Electrophorus
- Electroscope
- Electrotherapeutics
- Fluorescence
- Fuze, or Fuse
- Galvanometer
- Gutta Percha
- Induction Coil
- Lead
- Leyden Jar
- Lighting
- Meter, Electric
- Motors, Electric
- Nitrogen, Compounds
- Ohmmeter
- Oil Engine
- Oscillograph
- Potentiometer
- Power Transmission
- Röntgen Rays, Apparatus
- Rubber
- Sal Ammoniac
- Sodium, Compounds
- Sulphuric Acid
- Surgical Instruments
- Telegraph
- Telephone
- Thermometry, Electrical
- Traction, Electric
- Tramway
- Transformers
- Units, Physical
- Vacuum Tube
- Ventilation
- Voltmeter
- Wattmeter
- Wheatstone’s Bridge
- Wire
- Zinc
CHAPTER XII
FOR MERCHANTS AND MANUFACTURERS OF CHEMICALS AND DRUGS
A Factor in All Industries
The chemical and drug industry is not only in itself an enormous business, but it supplies essential materials for almost every branch of manufacturing. Chemical products are employed in our buildings, our clothing, our food; we come into the world and go out of the world with the odour of chemicals about us. The manufacturer or dealer cannot analyze all the influences that affect his market, and when he tries, as he must, to consider the future of the trade, to reckon with the channels of demand that will arise in the course of new applications of chemical products, he is facing all the problems of all the industries.
The variety of raw materials from which chemical products are derived, and the activity with which new sources are discovered and developed, are almost as bewildering. Only a century has passed since coal-tar was first distilled, and to-day no chemist would venture to fix the limits of its industrial possibilities. Electrolysis has been in use since 1804, and yet the future of the world’s wheat supply probably depends upon processes, as yet hardly beyond the experimental stage, of utilizing atmospheric nitrogen.
In connection with so comprehensive an industry, the uses of the Britannica are so manifold that this whole Guide might be devoted to them. Articles on every manufacturing process touch upon the use of chemicals. The articles on countries, states and cities are full of relevant information; and there is hardly a scientific article that would not be helpful. But the 40 general articles on chemistry, the 350 on chemical compounds, and the 75 on manufactured products call most immediately for attention; and, with the aid of other chapters in the Guide, the reader who desires to go further will easily find his way.
Articles on Chemicals