The Atomic Instrument Company was started by Leonard Cronkite and Hugh Stoddard in 1946 making “Apparatus for Nuclear Measurements” for the nuclear industry. In 1947, they introduced a line of health physics instruments. Atomic Instrument Company was located at 158 and later 160 Charles Street in Boston, Massachusetts in 1947. They later moved to 84 Massachusetts Avenue in Cambridge in 1951. In 1956, they merged with Baird Associates to form Baird-Atomic.

The Model 1001-A was a beta, gamma sample monitor in 1947. It was called the Radioactivity Demonstrator and was designed for lectures, classroom or laboratory demonstration of radioactivity principles. It could regulate Geiger-Mueller tubes from 500-1500 volts and operated on AC. The settings are x1, x10 and x100 and readings in either mR/h or cpm. It has a battery test on the top of the device. It had both audio and visual indicators for the demonstrations.

Atomic Instrument Model 1001A 1949

The Model 401-X was introduced in 1949. It was a Cutie Pie style unit with an ionization chamber detector. At the end of the unit near the pistol grip was a meter. The chamber was 2-5/8” diameter x 4.5” long. It had two ranges of 0-100 and 0-300 mR/h. It used one mercury cell and one 22.5 volt battery. The unit was about 10 inches long and weighed about 5 lb. Variations of this unit are offered as Models 403 and 405 in 1950.

Atomic Instrument Model 401-X 1949

The Model 404A was introduced in 1952. It had a single logrithmic scale covering the full instrument range 3-3,000 mR/h. No scale switching is required. The unit is designed to give the user a quick reading of exposure and decease the time personnel are exposed to high intensity radiation. It can detect beta and gamma. It is lightweight, has simple controls and can be easily decontaminated. It is the ideal survey meter for nuclear, medical and industrial laboratories.

Atomic Instrument Mod 404A 1953

The Model 409 Laboratory Monitor has three range settings 200, 2000, and 20,000 cpm. It is small, compact and designed for contamination monitoring. The high voltage is adjustable to correct for the Geiger tube being used. The unit measured 3.75” x 4.75” x 6.75”.

Atomic Instrument Model 409 1951

The Model 410 was introduced as a laboratory monitor in 1950. It could be used with a Geiger probe or alpha scintillation probe. It measures 12.5” x 11” x 10.5” and weighed 23 lbs. It had a regulated voltage from 500 to 2000 volts and operated on AC. It had a four decade range from 200 to 200,000 cpm. It had a large 4.5” meter and speaker. It came in a hand rubbed blonde oak cabinet.

Atomic Instrument Model 410 1950

The Cutie Pie Model 414 was introduced in 1951 as a Logrithmic Radation Survey Meter. It provides radiation measurement from 3-3,000 mR/h. No scale switching necessary. It detects x-ray, gamma, and beta radiation. Time constant varies with intensity. It has long life filament batteries. Internal calibration standard permits instrument calibration without radiation source. It has a high visibility quick read meter.

Atomic Instrument Model 414 Ad 1956