This week’s cover is an impressive view of a navigation lock at Guntersville Dam, Alabama, which is part of the United States Government’s colossal scheme for promoting economic recovery in the Tennessee Valley. Guntersville Dam is one of a series of dams designed to make the Tennessee River navigable in all conditions over the 650 miles between Knoxville (Tennessee) and Paducah (Kentucky).
The remarkable ways in which diamonds are used in engineering, described by Dr Malcolm Burr. The article is concluded from part 31.
Solving the Smoke Problem
Engineers and chemists are now closely co-operating to solve smoke and waste gas problems arising from the growth of power supply on a large scale. The main object is to lessen the damage caused by the emission of grit, dust, tar and harmful acids. One of the problems which have arisen from the building of giant power stations, in Great Britain particularly, is the problem of fighting the smoke menace. Atmospheric pollution from the waste gases of modern power stations is causing a great amount of damage. Not only are stonework, metal and paint impaired by the grit and acid gases discharged into the air, but also the health of human beings is affected. Chemists and engineers, in recent years, have done much research work with the object of preventing this form of pollution. In this chapter, Rolt Hammond describes a remarkable new process which not only removes injurious matter from flue gases before they are discharged into the atmosphere, but also converts the sulphurous products into sulphur. Processes of this nature help to lessen the contamination of the air in large towns.
The Tir John Power Station
DESIGNED TO BURN ANTHRACITE - the Tir John power station at Swansea, South Wales. Anthracite, which consists almost entirely of carbon, burns with a smokeless flame. Designers of anthracite-burning power stations do not, therefore have to allow for the treatment of waste gases.
Control of the Tennessee River:
Photogravure Supplement - 2
THE UPSTREAM FACE OF NORRIS DAM, seen from the top of the mixing plant on the west abutment during the building of the dam. The semicircular structures at the base are “trash-racks” or filters covering the openings through the dam. The masonry section of Norris Dam is 1,570 feet long; the dam is situated on the Clinch River, an important tributary of the Tennessee River.
Control of the Tennessee River
A vast engineering project involving the expenditure of more than £75,000,000 has been devised to regulate the flow of the Tennessee River and to combat erosion of the surrounding land. Whatever political opinions one may have, it is impossible to view with anything hut admiration the vast schemes that President Roosevelt has recently put into operation to promote economic recovery in the USA. One of the most remarkable of these schemes is described in this chapter by Harold Shepstone. A special Act of Congress in May 1933 created what is known as the Tennessee Valley Authority, popularly known by its initials TVA. The task of this body is to regulate the Tennessee River, which flows for 800 miles before it joins the Ohio. The objects of this control are many. They include the use of water power for generating electricity, which is to be introduced on a regional system for use in homes and in factories. They include the development of river navigation. In addition, by checking erosion, TVA will produce radical changes in the variety and yield of agricultural produce in the Tennessee Valley.
The scheme involves the building of a number of high dams which, in addition to assisting the other aims of TVA, will serve also to reduce the extent of floods in the Ohio and Mississippi Rivers, to which the Tennessee River contributes a considerable portion of the total flow. Work has been going on for some years, and many enormous dams have now been built. Elaborate experiments have been made to improve agricultural conditions and furnish hydro-electric power. The scheme is so vast that it is not expected to be completed for another five or six years, though it is already one of the wonders of engineering. Two turbines, each generating 66,000 horse-power, are already in operation. They are supplied with water stored by Norris Dam, the masonry section of which is 1,570 feet long. At the base of the dam in the spillway section the structure is 204 feet thick, and there is a difference of 265 feet between the foundations of the power house and the level of the roadway along the crest of the dam. This chapter is accompanied by a striking photogravure section showing various aspects of the Tennessee Valley scheme in course of construction.
SOME OF THE PULSATOR TABLES of a mine at Kimberley, South Africa. Concentrates from the washing pans are passed over shaking tables, or pulsators, and again washed, on inclined tables covered with greases, to which the diamonds adhere.
Control of the Tennessee River
AFTER THE OHIO-MISSISSIPPI FLOODS of 1937, Norris Dam during the overflow period after the storage of flood water. Norris Dam is 265 feet high and 204 feet thick at the base of the spillway section. At the crest of the spillway are three hydraulically-operated gates, each 100 feet long.
Tramway Cars and Trolley Buses
More than a thousand million passengers are carried by tramway cars in one year in London alone. The trolley bus is replacing the tramway car in many places, but the two systems of transport are of great importance in most cities and towns. Electric traction is a subject of absorbing interest. The first electric tramway in Great Britain was installed in Leeds in 1891. Since that time tramway cars have appeared in almost every large town. During the year 1934-35 more than a thousand million passengers were carried in electric tramway cars in London. In many places, however, this form of transport is being superseded by the trolley-bus. The first rails for tramway cars in Great Britain were laid at Birkenhead as long ago as 1860. At that time, however, the cars were drawn by horses. It happened that a few months ago Birkenhead withdrew its electric tramway services. It was a great civic occasion. A specially illuminated car helped to celebrate the end of the tramway era in Birkenhead.
In Birkenhead electric traction has been replaced by motor traction, but in London and many other cities the tramway cars are being gradually replaced by trolley-buses. The operation of these vehicles is described by Sidney Howard in this chapter.
Glasgow Corporation Tramway Car
EXPERIMENTAL TRAMWAY CAR built by the Glasgow Corporation Transport Department in an effort to produce an ideal vehicle incorporating all modern refinements. The seating capacity is sixty-five, and the car has a length of 34 feet and a width of 7 ft 4 in.
Pickwick Landing Dam, Tennessee
ONE OF THE LARGEST NAVIGATION LOCKS in the world under construction at Pickwick Landing Dam, Tennessee. The building of the dam has caused the formation of a lake 53 miles long.
Removing the Body of a Tramway Car
REMOVING THE BODY OF A TRAMWAY CAR from its trucks by means of an electric hoist. The work of an overhaul shop is divided into two sections, one dealing with the body and the other with the truck and motors. The truck and motors are replaced with reconditioned parts, and the body is placed on a ropeway which conveys it through the various sections of the body shop. Here body work, wiring and electrical equipment are examined.
Story of the Cinematograph - 1 (Part 1)
One of the largest industries in the world had developed from the invention of a scientific toy. The cinema camera, in addition to its entertainment value, is of incalculable service to the engineer and the scientist. This chapter is by F E Dean and is concluded in part 33. It is the second article in the series Invention and Development.
The second part of the Story of the Cinematograph appears in part 35and part 36.
Control of the Tennessee River
Photogravure Supplement - 3
NAVIGATION LOCK at Wheeler Dam, Alabama. This lock, which is 60 feet wide and 350 feet long, has a lift of 50 feet. At the north end of Wheeler Dam is a cut-off wall, 220 feet long, which is built across the possible location of a future lock. Should it be found necessary, this second lock will be 110 feet wide and 600 feet long.
Le Prince’s Single-Lens Camera
FORERUNNER OF THE MODERN CINEMATOGRAPH CAMERA -Le Prince’s so-called single-lens model. One of the two lenses on the left served merely as a viewfinder. The contrast between early machines, such as this, and the modern cine-camera is a striking testimony to the rapid development of an epoch-making invention.