Argus (Melbourne, Vic. : 1848 - 1957), Thursday 16 February 1922, page 11


ENGINEERING.

AVIATION NOTES.

By METRE.

Container Railway Car.

In order to reduce the time required for loading goods, the New York central lines have introduced what is termed a "con-tainer railway car." This is a car with low sides, and it is designed specially for carrying a number of containers constructed to fit the car floor. These containers might be described as light, steel safes, which after being loaded with freight by the consigner would be carried to the sta-tion in a motor-lorry and there would be lifted by cranes and deposited on the car. Ordinary cars are built to take five con-tainers. This method, of course, making, for very rapid loading and unload-ing, adds largely to the capacity of the rolling-stock equipment.

In a paper read before the American Society of Mechanical Engineers, Mr. Wal-ter C. Sanders, an officer in the equipment department of the New York central lines, said that the cars were introduced last year by Mr. A. H. Smith, who is the pre-sident of this group of railways. It was hoped that mail, express, and freight rob-beries, and breakages, delays in checking and handling would be greatly reduced by this system. Loss of and damage to freight had grown so much in recent years that it was now one of the heaviest leaks in the transportation industry.

The container car, Mr. Sanders went on to say, would reduce the cost of packing and crating, for goods packed in paste-board or even in ordinary paper would be protected from breakage, theft, and water or weather damage. The locked containers could remain either on station platforms or else at the stores of the shippers for un-loading or loading whenever this might be convenient, and in this way there would be no demurrage of costly rolling-stock. At present there were three container cars on the New York Central group which were used carrying mail matter and valuable freight, such as silks and woollens. Three new mail cars of improved design were being constructed, and the introduction of refrigerator and tank container cars was under consideration.

For goods that are carried on an ex-press car attached to passenger train, the containers are somewhat smaller to meet the requirements of the express consign-ment business. A 61ft. 3in. car will carry nine express goods containers. The size is 9ft. by 6ft. by 7ft. 4in., and the door is 6ft. by 3ft. The carrying capacity is 7,000lb.

Whether it is the railway company or the shipper that supplies the containers is not stated. Presumably it is the ship-per— or, at any rate, it will be when the system is introduced on a large scale, for otherwise there might be serious inconveni-ence, due to the demurrage of containers.

The New York central lines have made

a most interesting experiment, and so far the experience with the container-car sys-tem goes to show that its success is as-sured. --------

Aeroplane Catapults.

The United States naval authorities are experimenting with catapults for launch-ing aeroplanes from warships. The cata-pults are in the form of turntables, and the most suitable type can be installed on any ship. This, it is considered, is the best answer to bombing aeroplanes at-tacking naval craft, for here "dog will eat dog." As the turntable catapult can launch a plane in any direction, there should be no need for the ship to locate formation when helping to repel an aero-plane attack. The propelling power for the catapult is compressed air. --------

The Arctic Steamer Quest.

The arctic steamer Quest, chartered by the late Sir Ernest Shackleton for his Antarctic expedition, though only 111ft. in length all over, has a range of 9,000 miles with 200 tons of coal in her bunkers. She was built in Norway in 1917, and was in-tended for sealing. The hull, which is enormously strong, is constructed of pine and white oak, with steel reinforcements of the bows. The boiler is of the "Scotch" type, and the engine is a two-cylinder com-

pound. The little ship is equipped with an aeroplane and a wireless plant. --------

Giant Turbo-Alternator Sets.

In an article by Professor W. Reichel, published in a German technical journal, it is said that turbo-electric generators may be built in sizes up to 160,000 kva., and the most serious obstacle in the way of accomplishing such constructions lies in the difficulty of the transportation of such huge machines by railroad, necessita-ting their assembling and, in particular, winding on the spot of installation, a pro-cess not always attractive.

The use of giant machines of 160,000 kva. at 1,000 r.p.m. is suggested in a central station with six units, one being a standby. Such a plant would have a normal load of 400,000 kw. and a peak load of 500,000 kw., with a total output per year of, say, 2,000,000 kw. hr. Five such central stations would have been sufficient to satisfy the entire demand for electric power in Ger-many. For steam turbines driving these generators are suggested double units with steam admission in the middle, 16 gauge to 17 atmos. pressure at the turbine inlet and 20 atmos. pressure on the boiler, with a steam temperature of 350 degrees Centi-grade at the turbine inlet valve.

In view of the great consumption of fuel and water of condensation, it is obvious that economically such big plants should be located only near a large coal supply and also near a large river. As-suming that coal would be delivered 300 days in the year, this would mean that 7,500 tons per day would have to be re-ceived into the plant and be distributed either to the boiler rooms or to the bun-

kers.

The general conclusion to which the author comes is that at present the limit to the size of electrical generators is set mainly by the demand for power. --------

Old Files Renewed.

It is stated in the "Scientific American" that old files may be renewed by first clean-ing them with a "file card" and afterwards placing them in a mixture of 4oz. of wash-ing soda and one quart of very hot water, in which mixture they are then scrubbed with a brush to remove oil, dirt, &c. The acid mixture to which the files are then transferred, consists of 4oz. of sulphuric acid in one quart of water. It should be remembered that when diluting sulphuric acid with water sudden heat is developed such that if the water is poured upon the acid dangerous spattering will occur. The acid should always be poured into the water very slowly and the solution stirred with a piece of wood or a glass rod. The old files remain covered in the solution for from 10 to 12 hours, after which they are thoroughly washed in water, dried, and

oiled. --------

American Air Mails.

The following particulars concerning aerial mail services in the United States have been forwarded by the Society of the Australian Aircraft Owners :—

In May, 1918, aerial mail services were established in the United States of Amer-ica. After the first year's operations, the control of the services was handed over by the War department to the Postal de-partment. At the same time, the charge for aerial correspondence was reduced from six cents an ounce to two cents, which is the rate of postage on letters carried by

train.

Twelve months later, a report was issued which showed that a profit of 10,000 dollars had been made ; that the cost per mile had dropped to 50 cents ; and that the saving of time now effected over the fastest rail-road train between New York and Chicago would enable the Postal department to make a saving in space equal to more than twice the cost of an air mail service on

that route.

As aerial mail services are now about to start operations between Adelaide and Sydney and Brishane, it is interesting to note that the United States report re-ferred to contains the following state-

ment :—

"The success of the aeroplane in carry-ing the mail, together with the great de-velopment that has taken place in speed, and quantity of mail that can be carried, makes it improbable that air transporta-tion, whether by Government or commer-cial lines, will ever be stopped ; but will increase from year to year, by leaps and bounds, especially over long distances."

There is now a complete service opera-ting daily across the whole width of the American continent, reducing the travel-ling-time between New York and San Francisco by 24 hours. It is claimed that the Transcontinental Air Mail is un-equalled by any other aerial undertaking elsewhere. During the year ending 30th June last, more than 23,000,000 letters were carried over a total distance of 540,244 miles, at less than it would have cost to transport and deliver them by rail. No additional postage is charged. --------

Answers to Correspondents.

T. McC. (Colac).— It would he better for you to write for the particulars. As far as suggesting practical new uses for rubber is concerned, you would have a formidable table for many hundred

suggestions are sent in.

"Navis" (Williamtown).—1. With a very small high-pressure cylinder, receiving steam for nearly full stroke, you would, of course, reduce the range of temperature in that cylinder, and the losses due to range. But these losses would still occur in the low-pressure cylinder. Another objec-tion is that the engine would not be easy to bal-ance. 2. The latest P. and O. steamers have quad-

ruple expansion engines.

"Novice" (Yarraville).— In starting from cold the exhaust pipe and vaporiser are cold, and can-not be used to heat the mixture. You could start by applying petrol to the float chamber, or else by heating the chamber with a primus.