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Updated: Jun 4, 2023

John Hays Hammond Jr. May 22, 1922

John Hammond Jr. (April 13, 1888 – February 12, 1965) was a wealthy American inventor known as The Father of Radio Control. Hammond’s pioneering developments in electronic remote control are the foundation for all modern radio remote control devices, including modern missile guidance systems, unmanned aerial vehicles (UAVs), and the unmanned combat aerial vehicle (UCAVs).

At an early age Hammond become friends with Thomas Edison and Alexander Graham Bell where they became his mentors. He also became friends with Nikola Tesla where they would work together on various ideas and projects over the years.




Not only was Hammond a very successful inventor, he was also responsible for the construction of Hammond Castle (which he named Abbadia Mare, translated as Abbey by the Sea) in the Magnolia area of Gloucester, Massachusetts. It was built between the years of 1926-29 and is composed of modern and 15th-, 16th-, and 18th-century architectural elements. Not only was this building the family home, but it also housed his elaborate collection of ancient artifacts that he sought from around the world, and also served as a laboratory.

Hammond certainly wanted to be remembered and this grand building was his way of doing just that. In 1924 he wrote:

In a few years after I am gone, all my scientific creations will be old-fashioned and forgotten. I want to build something in hard stone and engrave on it for posterity a name of which I am justly proud.

Various photos of the exterior of Hammond Castle (Abbadia Mare). Photo's taken August, 2021.



Hammond had a fascination with the occult and had long been curious about the capabilities and impacts of sound waves and electromagnetic charges on the emotional lives of human beings. From 1951-52 he conducted a series of telepathic experiments (funded by the Parapsychology Foundation) on Eileen Garrett who was a well known psychic at the time. The experiment consisted of placing Garrett in a Faraday Cage, which is designed to keep out electromagnetic waves, this was to determine whether ESP (extrasensory perception) used electromagnetic frequencies as a carrier wave.

A description of the experiment can be found in the book, Color Healing: Chromotherapy:

Science was represented by a team of top-drawer electronics physicists, headed up by John Hays Hammond. Parapsychology’s representative was Eileen J. Garrett, president of the foundation. The scientists undertook to devise assemblies of electro-magnetic instruments under conditions that would rule out any possibility of ether-waved telepathic or emotionally-conveyed contact between Mrs. Garrett, as the clairvoyant, and the science team. She was placed in a series of three Faraday cages, one inside the other…A scientist was stationed inside the cages with her. A tape recorder was placed in the inner cage, another was set up outside. A quarter mile away, a random switch to turn on and off an electrical current was placed in a hidden location.

It is rumored that these experiments were conducted in the castle’s Great Hall and that the Faraday Cage became so hot due to the electrical currents running through it, the prolonged exposure to heat caused the stone floor beneath to fade. Unfortunately we could see no evidence of this on ourselves, but we shall definitely take a more thorough look on our next visit.

The conclusion Hammond determined once the experiment was over (according to the book Wizard: The Life and Times of Nikola Tesla) was that since Garrett could still communicate telepathically with the science team through a series of ESP tests while she was in the cage, it proved ESP was not transmitted on electromagnetic frequencies.



After talking with one of the guides regards any ghost sightings, we were told that various visitors over the years have reported seeing a black cat walking around the castle. Hammond was certainly a cat lover and was buried in a steel casket in a mausoleum on the property, along with three of his Siamese cats still preserved in jars. Sadly, his body had to be removed in 2008 and reburied in the outdoor courtyard after vandals broke into the mausoleum and stole the cats. Are the sightings of this mysterious feline that walks the rooms of the castle a spectral entity looking for it's former owner?

John Hammonds burial site can be found on the grounds. His death mask is also on display, although this was made whilst he was still alive. Photo's taken August 2021.

This location is not so much a Historical Horror, but is certainly Historical in the field of paranormal experimentation. A must to visit due to it's collection of ancient artifacts, the telepathic experiments that John Hammond did here and the mediumship and seances that his devout spiritualist wife Irene would host. We can only imagine what otherworldly things that may be lurking in the corners of this fascinating property, it is worthy of an investigation for sure!


For more photo's of our visit to this wonderful property, visit out Facebook page.

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