tions. Military and civilian agencies concerned agreed that the method should be recommended as a standard procedure. A meeting was called by the National Research Council on 1 October 1951. The investigators presented their findings to interested civilian groups, and on 6 December there was a nationwide press release. The American Red Cross and other agencies which had been represented at the National Research Council Meetings accepted the recommendation.

Thus, a research program costing $25,000, supported by the medical services of the Armed Forces and by the Army Chemical Corps, resulted in the nationwide adoption of the back-pressure arm-lift method of artificial respiration.

AUTOMATIC COLONY COUNTER. The Army Chemical Corps, at its Biological Warfare Laboratories at Fort Detrick (Md.), has recently developed a new device for the automatic counting of bacterial colonies, which will relieve bacteriologists everywhere of a great deal of labor.

Biological research along various lines often requires making an accurate count of bacteria. A common method is to spread a small amount of fluid containing the bacteria on a solid surface of agar, largely isolating the individual microorganisms from one another. After the plate has been suitably incubated, each isolated "seeded" bacterium has produced a visible colony. The colonies can then be counted, and their number approximates to the number of bacteria in the (known) amount of liquid which was originally applied to the plate. But the counting, in the past, has been a very laborious and time-consuming process.

In the Chemical Corps technique, which is based on a British method of electronic operation, the count of colonies is made by "scanning" the surface of the incubated plate with a minute ray or pencil of light from a cathode ray tube, much as in the picture tube of a home television set. The ray moves across the Petri dish one thousand times per second, completely scanning the agar surface by advancing .0035 inches (about the width of a hair) for each line of scan. Changes in optical density

between the transparent agar and the opaque colonies are recognized by a multiplier phototube.

The operating secret of the device lies in the action of its "memory"-a quartz ultrasonic delay line-which keeps track of the details of the previous tour of the scanning pencil across the dish in relation to its current scan. Electronic circuits compare these two records to determine which colonies are being encountered for the first time. Each new colony is counted in the registers of the machine. Repeated scans of a previously recognized colony are cancelled out by the comparing circuits, and hence not counted.

Development of the technique has been completed, and laboratory testing is in progress. It will probably have other uses, such as counting metallurgical specimens and similar small objects. PROTECTION AGAINST INDUSTRIAL GASES AND VAPORS. An important peacetime service of the Chemical Corps has been the development of various masks as protection against the deadly gases employed in many industries, and the detailed study of methods to protect against other forms of poison. Since all of these poisons have at one time or another been considered as possible chemical warfare agents, the Chemical Corps is familiar with their properties. The knowledge thus gained is freely offered to industry.

Carbon Monoxide. This gas is difficult to remove from the air, due to its high volatility and to the fact that it is chemically inert. For protection against it, the absorbent in the mask must react very quickly, must be reasonably hard, must offer moderate breathing resistance, and must be capable of quantity production. The Chemical Corps devised a mask to meet these rigid requirements, and it was adopted by the Navy for submarine crews and by many industrial firms. Most of the commercial carbon monoxide masks can trace their lineage back to this model.

Ammonia. Ammonia fumes are encountered most frequently in ice plants and in handling cylinders, but also in fire fighting and in miscellaneous chemical plant work. As the war gas mask canister did not afford satisfactory protection against ammonia, a special

canister had to be developed, and this the Chemical Corps succeeded in doing. The mask it devised afforded complete protection against low concentrations of ammonia for a considerable period. An intense skin irritation would give ample warning of the presence of a higher concentration of ammonia, and the canister would protect the wearer for a longer time than the irritation could be tolerated. When a small amount of ammonia could be smelled, it was a warning that the canister was nearly exhausted.

Mask for Fumigation Work. Another type of mask developed by the Chemical Corps, which has been of peacetime use to the Public Health Service in fumigation work, is one designed to protect against a poisonous gas, hydrocyanic acid, and a tear gas, cyanogen chloride. As a result of a thorough study of absorbents for these gases, two chemical compounds were found particularly effective. The absorbents were placed in a modified war canister. By an ingenious arrangement, when the canister was exhausted, tear gas rather than poison gas penetrated and gave warning to the wearer.

There are many commercial counterparts of these masks, most of them based on the researches of the Chemical Corps. As a result it is cheaper today for the Corps to buy civilian masks than to make its own; and the Army models have been declared obsolete.

HYDRAZINE. A few years ago medical science discovered that tuberculosis responded to treatment with a chemical called hydrazine. The Ordnance Corps was thereupon able to make it available to the medical world, for it was already being produced in quantity as

a guided missile fuel.

THE MEDICAL MUSEUM. This institution was started in 1862 by Surgeon General William A. Hammond. It is now one of the four major departments of the Armed Forces Institute of Pathology in Washington, D.C. It collects and exhibits materials of professional and historic importance, for advanced study by physicians and allied scientists, and for the education of the public. Some 200,000 persons visit it yearly. The museum provides guided tours, motion pictures on medical subjects (Sundays only), and lectures on the history of medicine for professional and lay audiences. It is open daily to the general public.

THE NATIONAL LIBRARY OF MEDICINE. This was founded in 1836 by Army Surgeon General Joseph Lovell, as a small office library for the Surgeon General's use. In 1865 Dr. John Shaw Billings began to expand it. Today it has become, in the words of the Hoover Commission Report, "the largest and most important medical library in the world." It has more than 650,000 bound volumes, and is growing at the rate of over 25,000 per year. Its "Current List of Medical Literature" indexes more articles than any other medical index, is more up to date than any other, and is widely used by the civilian medical profession. It has served civilian agencies and health workers since 1892.

Until 1956 the library was known as the "Armed Forces Medical Library." In that year Congress placed it under the jurisdiction of the Public Health Service, and it was given its present

name.

The demands of the Army for weapons and equipment have many times resulted in new devices, materials, and processes which have proved to be of great industrial value. Some examples are given below.

SYNTHETIC RUBBER. Research in the use of synthetic rubber for tires, and tire proof-testing, far more extensive and conclusive than commercial producers would normally find justifi

able, has been conducted since early in World War II by the Army Ordnance Corps. It has made the nation independent of natural rubber imports in any emergency period, and is responsible for the wide use of synthetics in tires and tubes for cars and trucks. In many respects-toughness, for example-these synthetics are superior to rubber.

natural

THE JEEP. This characteristically

American vehicle, with its characteristically American name, has come into wide civilian use.

Credit for the original design may not be claimed by any single individual or manufacturer. Quartermaster Corps motor engineers, both military and civilian, at the Holabird Quartermaster Depot did the bulk of the work, in cooperation with unit manufacturers and the American Bantam Car Company's engineers. The present body design is based almost entirely on Holabird drawings, while the axles and transfer case were designed by the Spicer Manufacturing Co. of Toledo.

The evolution and development of the jeep extended over a decade. Work done in the early 1930's clarified the basic requirements of the vehicle desired. It must be small, tough, and high powered for fast driving over rough or marshy ground; it must have a low silhouette for concealment; and it must serve as a carrier for a few men or for light weapons. A vehicle of this general character was assembled from salvaged motor units at the Infantry School in 1936-7, and exhaustively tested. In 1937 and 1938, test model chassis assemblies were obtained from the American Bantam Car Co. Under a new project a 3passenger light-weight open body was devised; and in 1940, 70 of the cars were ordered from Bantam and tested. Based on these tests new specifications were drawn, and the vehicle went into quantity production.

Officially designated as "truck, 2-ton, 4 x 4," it was originally called a "light command and reconnaissance car"; but public fancy christened it "jeep," and jeep it has remained.

"Zelan," a DuPont product, in 1938 made it possible to produce clothing with a certain resistance to penetration by rain. However, the development of water resistant textiles was greatly accelerated in World War II. A number of treating compounds were devised, from which a study by the Quartermaster Corps permitted the selection of a few that are still in use. Their limitations are recognized.

Mildew Resistance. In World War II there was a heavy demand for mildew resistant fabrics, especially for tentage. This led to the development of improved mildewcide agents, which had low toxicity to the human skin but were extremely effective against a broad spectrum of microorganisms. One such compound, Copper-8-quinolinolate, is in widespread use in the Armed Services today where copper compounds can be tolerated. For other situations dihydroxydichlorodiphenyl methane is principally used.

Shrinkage. Before World War II industry had not adequately studied the problem of preventing shrinkage of textiles, expecially wool. The Quartermaster Corps of the Army led the way with an aggressive research program. Before the end of the war, knitted items such as socks and underwear were being completely treated. Since then such treatments have been extended, and today a large proportion of wool textiles are so treated. There have been similar advances in shrinkage control of cotton fabrics, due again to military demands.

Fire Resistance. The development of a permanent type of fire resistant treatment for clothing has been a major contribution of QM R&D. Finishes have been developed which will resist up to 20 launderings and retain their complete effectiveness.

A combined fire, water, weather, and mildew resistant treatment for tentage was developed just before World War II. Over 700,000,000 yards of fabric were processed during the war and used successfully by the Armed Services.

Other Treatments. A treatment of textiles has been devised to inhibit the formation of static electricity. This is particularly important for application to some of the new synthetic fibers which are non-water absorbent. Thus, when

used in cold climates with extremely low humidities, the prevention of the formation of static is of marked importance.

Treatments have also been worked out for the absorption and inhibition of chemical warfare agents, especially mustard gas in both gaseous and spray form.

IRRADIATION

TREATMENT

OF FOODS. Military necessity drove Napoleon to uncover a new method of preserving food for his armies. Since the basic effort of Francois Appert, a century and a half of uninterrupted development has given mankind its present insight into the technology of the canning preservation of food. Today, with the help of over 300 cooperating research scientists in over 100 university, industrial, and governmental laboratories, the Quartermaster Corps is working on a research and development project, supervised by the Food and Container Institute, for the peaceful application of atomic energy to this field.

The Army sponsored the project because it wanted early results, and felt that industry could not afford to pay for the necessary research. It was started in 1953. Shortly thereafter contracts were let for the use of experimental gamma and beta radiation sources; and foods were screened to find out how radiation affected them.

As the work progressed the problem areas began to be defined more clearly, and at the same time potential gains were indicated. These included the inhibition of potato sprouting, control of mold growths, insect disinfestation in stored grains and cereal products, and the possible reduction in military subsistence refrigeration requirements. The use of the process to sterilize or pasteurize foods offered bright promise, since the irradiated food commodity is not necessarily subjected to the high heats of thermal processing, with their adverse effects on quality.

A pilot radiation processing plant is being established at Sharpe General Depot at Lathrop, California. Under the direction of the Office of The Surgeon General, about 20 representative irradiated foods are being used for long-term feeding tests on experimental

animals, to make sure that they are safe for human use. Volunteers at Fitzsimons Army Hospital at Denver have eaten such foods for shorter periods with no adverse effects.

The American civilian consumer, as well as the Armed Forces, will benefit by this effort. New food products, and preparations of present ones that will be easier to cook and serve, will be a boon to the housewife. Reduction in refrigeration demands and a longer shelflife will mean lower costs both for food distributors and for the public.

ANTIFOULING PAINTS FOR SHIP BOTTOMS. A major nuisance to ocean vessels is the accumulation of marine organisms on the hulls, which cuts down speed, increases fuel consumption, and reduces the ship's working time by the amount spent in drydock to clean the bottom. Barnacles are the principal offenders. They may accumulate to such an extent that they project several inches from the ship's hull. As these growths live only in salt water, it is possible to kill them by docking the vessel in fresh water, but the shells still adhere, furnishing resting places for new growths.

The Army Chemical Corps solved the problem by a toxic paint which destroys the organisms. Such a paint must meet several requirements. It must be permanent and must retain its poisonous properties during its own life. The poison must be powerful enough to kill or prevent the attachment of the marine organisms. Also it should preferably be made of domestic materials, to reduce costs.

Two different toxic paints were developed-a varnish type applied cold and drying by evaporation, and a hot plastic type which is applied in a melted condition and solidifies on cooling. The hot plastic paints are more expensive to apply and they form a heavier coat. They are much more durable, however, and are advised for use on long cruises. This type of paint was tested on the bottoms of several destroyers and gave excellent protection.

To protect the steel plating of the ship from the corrosive action of sea water, and also to prevent damage from the toxic paint, another type of paint was needed, to be applied to the plat

ing before the toxic paint was put on. This also has been developed by the Chemical Corps.

MAGNESIUM COATING. A researcher at Frankford Arsenal in Philadelphia, Mr. H. A. Evangelides, developed a process for putting onto magnesium a coating that would make this extremely light metal more useful. Called by his initials, the new HAE process has been widely adopted by industries where the metal is used or is processed for the use of others. The coating is brown, has a ceramic hardness, is resistant to the action of many corrosive chemicals, and is so resistant to heat that it will still hold together even though the applied heat melts the metal out from under it.

LENSES. At the beginning of World War II it was usual to coat the lenses of optical instruments, cameras, research equipment, fire control equipment, binoculars, etc., with a preparation which increased the transmission of light. This made the instruments much more effective, especially at dawn and at twilight, which was a great military advantage. However, the coating was weak, and could easily be wiped off by rubbing with the fingers. Army Ordnance contracts during World War II led to the development of new coatings for lenses, which did the same job but were tough enough to withstand any normal lens-cleaning operation. These new coatings are now used widely in commercial optical items.

AN EARLY INSTANCE OF "MASS PRODUCTION." The first essential, for mass production of a device which consists of a number of parts assembled together, is that similar parts be interchangeable between one assembly and another. In the days of individual craftsmanship which preceded the Industrial Revolution this condition was not normally met, especially as regards complex parts. The firing mechanism of a musket, for example, was tailormade to fit that particular musket; and the chances were that it would not fit into another musket of the same design, due to small variations in dimensions and in the finishing of surfaces.

In the War of 1812 our Army needed large numbers of muskets in a hurry. Eli Whitney, the inventor of the cotton gin, conceived the idea of making the parts with such great precision that they would be completely interchangeable. There was much skepticism as to his ability to do it. Whitney accordingly made an appointment to appear before a group of Army Ordnance experts. He brought with him enough parts to make a dozen muskets, placed the parts on a table in separate piles, and then proceeded to assemble the dozen muskets from parts picked at random. Convinced by the demonstration, the Army encouraged him by subsequent orders, and thereby contributed to the birth of mass production-otherwise "precision manufacture" of interchangeable parts.

The large-scale release of energy by the fission of atomic nuclei-perhaps the most portentous of all humanity's inventions-was first accomplished by the immense organization set up during World War II by the Corps of Engineers of the Army, with the code name of "Manhattan District." The District was established in utmost secrecy in June of 1942, and its real purpose was known only to a handful of top Government officials and scientists, who had been working for two years on a Government-sponsored project to build an atom bomb. Major General Leslie R. Groves, an Engineer officer, was selected to head up the project administra

tively. Plants were built in Tennessee at what came to be known as Oak Ridge, and at Hanford, Washington. The Manhattan District awarded design and construction contracts, assisted in recruiting skilled workmen, and supervised the entire project, up to and including the production of the test bomb and the bombs that were dropped on Hiroshima and Nagasaki in August of 1945. So well kept was the secret that designers working on plans for various phases of the plants were unaware of what they were to be used for; contractors who built the plants were equally ignorant of their use; and even the people who built the bombs,