Have you ever wanted to take a bath in your living room? Wished that your bathtub didn’t take up so much space? No? Well maybe E. J. Knowlton can convince you otherwise. Invented in Ann Arbor and patented in 1868, Knowlton’s “Bathing Apparatus” or "Universal Bath" was advertised across the country and made its way around the world. The lightweight, foldable bathtub was touted as being “Neater, Cheaper and more Convenient than a Stationary Bath, with no expense for Bath Room and Fixtures.”

The Inventor

Ernest John Knowlton, known as E.J., was born in upstate Manlius, New York in 1818. As a young man he and his older brother, Oliver, worked as contractors for the Erie Canal. The Knowlton brothers likely contributed their labor to a series of enlargements to the canal that began in 1836 and continued until 1862. During this period both of them contracted typhus fever, and Oliver died from the disease in 1840 at the age of 24. In his will he left his “dear sisters” Charlotte, Emeline, and Maria along with his “dear brother” Ernest about 48 acres of property in Portage, New York, and the money that he had managed to save. 

E.J. went on to teach school for 11 terms and travel for a number of years. At the age of 32 he married Roxana Potter and they settled in Michigan in 1850. They lived together in Canton, Lyon Township, and South Lyon, until they took up residence in Ann Arbor in 1867.

The couple called Ann Arbor home for 32 years, living at 24 N State St (an address that today is 322 N State St, the house having been replaced by the Duncan Manor apartment building nearly a century ago) for at least 25 of them. Their family grew to include three children, Ida, Jerome, and Mildred. Jerome was likely named to honor Oliver, whose middle name had been Jerome. E.J. was active in the community as a longtime member and leader of the Methodist Episcopal church, located at the northwest corner of State and Washington. He was also a strong advocate for the Union during the Civil War and helped find men to fill Ann Arbor's quota.

Productive Patenting

E.J.'s first appearance in the Ann Arbor City Directory in 1868 lists him as a “patent rights salesman.” Securing and selling patents was common in the era. Michiganders were issued 426 patents in 1876 alone, totaling one patent for every 2,787 residents.

The patents he maintained rights for included a “farm ladder,” which he created in 1863. It's distinction came from its dual use as both an A-frame ladder and a longer, single ladder that could be used when leaned against a tree or structure. Its patent lists fruit gathering and tree grafting as potential uses.

Three years later E.J. patented another piece of farming equipment, an improved “land roller” to break up soil to prepare it for crops. 

The Universal Bath

His pivot from agricultural equipment came in 1868 with his universal bathing apparatus. Described as a “flexible or pliable bathing-tub” it consisted of a wooden frame with a hammock like body of “oiled silk, or India-rubber cloth, or any other pliant water-proof material.” The frame’s hinged construction allowed it to be folded and stored away when not in use.  The patent describes the setup of the suspended tub:

 “One side of the frame A is secured to the front side of a bedstead [bed frame], by means of suitable straps or cords, and an adjustable leg is used for supporting the other side of the frame. Water is poured into the flexible body, and the person wishing to bathe enters the tub. The flexibility of the body allows it to accommodate itself to the shape of the person, bringing the water in more direct contact with the body of said person.”

Four years later, the patent was reissued with improvements to the invention. The updated drawings illustrate what was believed to set it apart from the competition. The new recommendation was to attach the frame to chairs, rather than using a bed frame and the formerly included leg. The bath’s “tub” portion could also be divided to create smaller sections. This setup could further reduce the amount of water required, which was crucial for potential consumers who didn’t have indoor plumbing and would have to painstakingly haul and heat water. Additional configurations are described: 

“Part of the frame to which the sack is attached, adaptable to sufficient inclination from the foot upward, to form certain specific adaptation, as for a hip, sponge, or foot bath where the bather may sit thereon with feet in the sage of the sack, just in front of the chair, on the floor or base-point, and sponge from head to foot in the most comfortable position, while the water all gathers around the feet” 

While the image of a man, sitting on a chair, surrounded by a “tub” can seem silly to us now, Knowlton’s apparatus was far from being the only bathing innovation in its era. Tubs specifically for sitting, sized just for children, and even bathtubs that folded up to reduce their footprint in small houses were not unprecedented. From 1880 to 1900 the Mosely Folding Bath Company produced a murphy bed-style bathtub that could be folded up to disguise itself as a wooden wardrobe with a mirror. Comparing it to the competition, Knowlton’s bath answered all of these needs with one product. 

Advertising directs interested parties to contact Knowlton at his home address of 24 N State St, but for some period of time he rented space from Herman Krapf who owned the planing mill at 529 Detroit St (the longtime home of Treasure Mart) to produce his baths there.

An Adaptive Apparatus

The advertising for the apparatus provides us with insight into the intended customer. “A complete arrangement for families, physicians, army men, students, miners, itinerants, everybody.” Most of the clientele listed were of an economic class less likely to own a home, or at least not one large enough to make a stationary tub worthwhile. Another advertisement preaches that “One of the most valuable agencies in contributing to the good health of all classes is the practice of judicious bathing.” 

The inclusion of physicians and army men stand out as using it for perhaps a different reason. The 1872 patent states that the “bath or baths may be used with great convenience and ease in the sick room.” If a person is ailing or has limited mobility and is unable to be easily moved to a stationary tub or bathroom, a portable bath may be a better solution. For army men, this would ring true for field hospitals.

We will never know what led Knowlton to pivot from farming equipment to portable bathtubs, but as a young sufferer of typhus who watched his brother die of the disease, Knowlton may have been acutely aware of the difficult, necessary work of bathing patients. Based on his ads he equated bathing with health. 

Invention Endures

Even as a resident of Ann Arbor E.J. still kept up his agricultural roots. The 1888-1889 city directory lists E.J. as a farmer of a secondary, 120 acre property in Saline Township. This continued connection to land management spurred further farm-related patents. In 1876, eight years after his bathing apparatus, he patented a combined hay rake and tedders for farm use. Three years later he patented another hay-tedder.

Knowlton additionally advertised a cistern guard he patented in 1874 on the trade cards he distributed for his universal bath. Even at age 76 he was still formulating improvements to his bathing apparatus. In 1894, after 20 years of experimentation, he patented a compound for waterproofing fabric. It was claimed to make closely woven fabrics “as good as a rubber coated sack” and “cost half as much.” The newly waterproofed tubs were advertised as having been tested in the homes of well-known families in Ann Arbor, where they were used for 5 years without issue.

Inherited Aspirations

Obituaries can only contain a brief summary of a person’s life, which underscores the importance of each detail included. In E.J. 's, he is said to have “had a great desire to go to college and in order to carry out this purpose he hired his time of his father.” Meaning, his father allowed him to seek work outside of his household to earn money. His work on the Erie Canal may also have been driven by his goal of saving enough to receive an advanced degree. 

While “he failed to acquire the college education he so greatly desired,” his son appears to have embraced the significance his father placed on continued education. Jerome stayed in Ann Arbor to earn his bachelors and then law degree from the University of Michigan. He started his own practice here, Sawyer & Knowlton, before joining the University of Michigan Law School. He was a law professor from 1885 to 1917 and held the position of Dean of the Law School from 1891 to 1895. From 1882 to 1885 Jerome also contributed to the community by serving as the Postmaster of Ann Arbor. 

Ida, the oldest Knowlton daughter, went on to marry another University of Michigan Law professor, Victor H. Lane, while E.J.'s younger daughter Mildred, married William T. Whedon, from Chelsea. These two moved to Norwood, Massachusetts where William worked as a tanner. Mildred passed away in 1897, two years before her father.

E.J. was remembered as “a man of most persevering character and indomitable courage, never being cast down by matters that would have discouraged ordinary men.” E.J., Roxana, and Jerome are all buried together in Forest Hill, and daughter Ida is interred there as well in the Lane family plot alongside her husband.