Yesterday I at last succeeded in transmitting sound by light. I used the principle of the manometric flame. The eye could not detect the variation of the lights at all but it was captured perfectly in the varying resistance of the selenium. My reproduction of the voice was perfect. Next, I have to set up an apparatus for very delicate photographing of the light variations. It is very interesting work.

-Ted Case in a letter to his mother from Yale University, February 1911

Developing the Tech, Part I

Developing the Tech, Part I

Developing the Tech, Part I

Developing the Tech, Part I

Developing the Tech, Part I

Developing the Tech, Part I

Explore the early inventions of the Case Research Laboratory, and the nativity of the technology which would transform the film industry forever.

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From a very early age, Ted displayed a fascination with the interplay of light and sound, and while he was in college attempted experiments with selenium cells to photograph sounds waves, and record the positives to a record. He referred to this early system as a “lightograph” and the process would foreshadow his later work. 

Case graduated from Yale in 1912 and returned to Auburn where, after his father Willard’s failed attempt to have Ted pursue a law degree, the two developed laboratories in the basements of their family homes at 196 Genesee St. and Casowasco (their summer home on Owasco Lake). In 1916, Willard Case inherited the Willard Mansion at 203 Genesee St., which would become Theodore’s home. With this acquisition, the two got to work converting an old greenhouse on the property into an operational laboratory: the birth of the Case Research Laboratory!

With the establishment of the Laboratory, the Cases began hiring researchers, including the recent Cornell graduate Earl Sponable, who alongside Ted would become essential in shaping the future of the Lab and sound film. Willard distanced himself from an active place in the Lab’s operations, and instead followed his son’s exploits eagerly until his death from the 1918 flu epidemic. Until the early 1920s, the Case Research Lab was in search of purpose, but the stellar scientific talent and significant investment on Ted’s part (nearly $100,000 a year to operate the Lab, or over $2.5 million in 2022 dollars) would place this greenhouse in an Auburn backyard on the world stage!

Let There Be Light (1916-1917)

In another life, Case may have had his name tied to a very different area of scientific innovation: solar panels.

I…put two copper plates in a solution of diluted salt water…to each plate is attached a wire, as in an ordinary electric battery, and to measure the current the other ends of the wire are fastened to a galvanometer. One plate of ordinary polished copper is kept in the dark. The plate in front of it, of black oxidized copper, is exposed to the light-preferably to strong sunlight. And there is no question that a current is set up.”-Ted Case describing photoelectricity experiments

In some of the Lab’s earliest work, Case developed a copper cell device that could measure currents produced by sunlight. Throughout 1916, Case and Sponable would perform a variety of photoelectricity experiments, taking a variety of minerals and crystals and testing their sensitivity to sunlight.  While the Case Research Lab would never develop an energy producing panel, the theories they published met acclaim, with one reporter from “The Evening World” dramatically proclaiming:

It was Emerson who dreamily advised you to hitch your wagon to a star but tomorrow you may, quite literally and practically, hitch your motor car to the sun. Also your vacuum cleaner, your coffee percolator, your electric hair tongs…For these are certainly all these golden and boundless possibilities in the just announced discovery of Theodore W. Case, who seems on the way to being Thomas Edison No. 2

The Case Lab’s exploration into photoelectricity was far from the first, with methods to detect and generate electricity from sunlight dating as far back as 1839. But as the innovation of electrified buildings and a national power grid were still very new creations, the discussions of how to produce electricity more cheaply and effectively had spurred a number of inventors including Case and his father before him to look into a variety of ways to create and store electricity.

To facilitate his work, Case purchased an audion amplifier from De Forest Radio Telephone & Telegraph Company. Finding the company representatives unable to answer all of his questions about the uses of the audion tube in his experiments, Case wrote a letter to de Forest directly to schedule a meeting and discuss his questions. This would mark the first in a long line of conversations that would lead to one of the most significant and tumultuous partnerships in film history.

As Case began to develop a professional reputation from publishing his work on photoelectricity, the US entry into World War I put an end to the Laboratory’s work in power generation. Like many of the industrial and research centers of the country, Case turned his attention to applying his creations for use in warfare.

Learn More About the History of Solar Panels

The Case Lab Goes to War (1917-1921)

In April, 1917, the US declared war on Germany and its allies and entered World War I. This led many of the nation’s inventors to turn their work to wartime applications. This included the Case Research Lab.

Ted believed his experimentation in photoelectricity could find practical application in wartime and defense. Case and his lab workers found quick success in experiments with a compound known as dyscracite, which they discovered showed photoactivity when exposed to long red light, and by extension infrared light. This led Case and his associates to test a new concept: a communication system using infrared light (which is invisible to the naked eye) to send messages from place to place.

How It Worked

The basic idea behind the system was fairly simple, and used three key components: an infrared emitting search light, an Eastman Kodak infrared filter which more or less eliminated all visible light emitted by the search light, and a cell which detected the infrared rays. A hand operated shutter would be placed in front of the search light, and would be cranked in such a way that the light would be emitted in a Morse code pattern. Originally a galvanometer would be used to detect the radiation pulses, but this was quickly transitioned over to a wireless receiver. This invention was essentially an invisible version of the light signaling system used by the Navy: which was exactly the branch of the military most interested in the Case Lab’s creation.

Learn How to Make Morse Code Messages with Light

Testing it Out

The earliest tests of the system were performed all over Auburn, with one attempt using electricity from Auburn’s operating trolley system that was then delayed due to bad weather (a familiar story for anyone living in Upstate New York). The first successful test was performed sending messages from the roofs of the mansion at 196 Genesee St. to the mansion at 203 Genesee St. A more successful test of the system’s range was performed in New York City with stations set up on top of the Sperry building and Woolworth Building, and across Prospect Park Reservoir in Brooklyn.

These successful tests attracted the Navy’s attention, and would eventually have Case operating from the Naval Experimental Station at New London, Connecticut. Ship to ship communications were effectively tested, and similar demonstrations would be performed for Allied forces across the Atlantic in England, France, and Italy.

An Inconvenient Peace

Case would continue to refine the signaling system well into 1918, finding a way to convert voices directly into infrared signals using a device known as a manometric flame. When successfully implemented, the device would have allowed signals to transmit directly into spoken messages rather than Morse code. The Case Research Lab developed significant partnerships with various companies throughout the war while creating the signaling system, including General Electric, Eastman Kodak, Western Electric, and a continued working relationship with De Forest Radio Telephone & Telegraph Company.

As Case and Sponable looked into ways to make the signaling system implement voice work, the armistice on November 11, 1918 ended the war and the need for active military research. While Case continued to push various uses for his system up into the early 20s, the lack of war need and the development of more popular systems like sonar made the infrared signals redundant. 

Fortunately, through the development of the signaling system, the Case Lab was also focused on finding more effective methods for the detection of infrared light, and through experiments with thallium he discovered a special kind of light bulb which he called the Thalofide Cell. He quickly patented his invention, and it was this creation out of all his innovations that would eventually come to shape Case and the rest of his lab partners’ futures.

Inventing the 20s (1920-1922)

In 1920, without the research demands of a wartime environment, Case and Sponable turned the Lab’s focus to a more generalized research capacity. At the center of the Lab’s growing commercial success was the versatile Thalofide Cell, which would receive interest from a variety of sources. Take a look at some of the experiments and inventions explored during this time period!

Measuring Daylight

In 1920, the Kleerflax Linen Rug Company wrote to Case asking whether the lab had used the Thalofide cell to measure daylight falling on material such as fabric. This inquiry prompted Case to develop a system to record daylight; using a CLR strontium or barium photoelectric cell attached to a Leeds & Northrup potentiometer. These cells were variations of the Thalofide cell, using different minerals to achieve the same effects.

Earl Sponable went to Philadelphia to discuss working with Leeds & Northrup to market the system.  Leeds & Northrup engineers thought that the combined system would work well, and agreed to conduct tests with the Case Lab cell and modify their apparatus for this use. The Vice-President of the company, Mr. C. Reding, assured the Case Lab that Leeds & Northrup would be interested in any plans that would help the sale of their recorders, but advised the Case Lab to develop the system fully and perform satisfactory experiments before taking the system to the Leeds & Northrup sales department. Their engineers suggested the Case Lab measure daylight with their system daily for an entire month first, and record their results. Sponable, Ted, and even Gertrude Case all helped monitor the results. 

Case, excited over the possibilities of such a system, thought it would be useful for weather bureaus, agricultural experimental stations, automobile headlight testing facilities, the dye industry, and street lighting projects.

Talking to Mars

In the 1920s, many prominent scientists theorized that there was likely intelligent life found on Mars, and the Case Lab performed experiments of their own to test the possibility. The experiment to establish communication was apparently a failure, as is recounted:

“On April 24th, 1920, Mr. Case and Mr. Sponable listened for possible communication from Mars, using the Thalofide cell at the focus of a 24” mirror and in connection with both the Dyscrasite apparatus and a 2 step audion amplifier such as is used in talking work. No positive results were obtained. The twinkling of the star was plainly evident upon the Dyscrasite apparatus and as this twinkling effect could be obtained from other stars besides Mars, it was evidently not due to any communication coming from Mars.”

Recording Sound on Film:

The Case Research Lab promoted their Thalofide Cell for a variety of uses. Case published a pamphlet advertising the cell to other labs and companies for experimental purposes. He also advertised the cell in “Science Magazine” and in “Popular Science.” This would prove fateful to the Case Lab’s future direction of developing sound on film.

The Thalofide Cell advertisements were seen by Lee de Forest, an inventor known for his work developing amplifying tubes for use in radio. In August 1920 he wrote to the Case Lab requesting further information on the cell. He wrote several more times during 1920, asking if Case had compared the cell to the Kuntz photoelectric cell, which de Forest had been using in sound recording experiments, and inquiring if the lab would do experimental work for him. In 1919, de Forest had applied for a patent for a sound recording system which he called Phonofilm.

As de Forest began to actively pursue sound film, Case became more aware of the ways in which his Thalofide Cells were being used in the device, particularly in the ways in which the Cells were not credited for their use in de Forest’s recordings. A tenuous business relationship between the two was established, and by 1922, the stage was set for the Case Research Lab to become a prominent player in bringing sound film to the world.

Other Experiments

  • Various methods for detecting X-ray and gamma radiation
  • Determining the drift of the earth using ether
  • Using radium to test phosphorescence in minerals
  • Using quartz and radium to kill streptococci bacteria (which are responsible for souring milk and causing diseases like scarlet fever and pneumonia)
  • A connection between the human ability to detect the color green and evolution from fish

Crediting for Images on this Page

Header: Self Portrait of Ted Case, c. 1908

Image: Scientific diagram of Thalofide Cell

Image: A “Lightograph”

Image: Case with copper cell device, c. 1916

Image: Sponable with copper cell device, c. 1916

Image: Signaling system c. 1918

Image: Unidentified Lab employee with infrared signaling system

Image: Patent drawing of infrared signaling system c. 1921

Image: Signaling system c. 1919

Image: Testing daylight monitoring equipment

Image: Thalofide cell