William Jay Barker was a Wigmaker/Hair Merchant in New York City from 1847 till his death in 1879. His wife carried on his business for him well into the 20th century. He started out at 622 Broadway, and by 1871, he had a second location at 1275 Broadway. In 1876, he moved to 36 West 29th, where the business stayed until around the turn of the century. An ad in 1888 called Barker a "Capillary Physician." By around 1900 the business had moved to 112 Fulton, and by 1930, it was at 412 Sixth.
In 1930, the Hirsutis was being sent out with a letter indicating that the users should buy a good stock, because they would be going out of business soon. At that time the product was still in a BIM container according to Harry Metzger. The letter said that they had been established in 1847, and that after 83 years of honorable service they would be retiring from the manufacture of B-H. The letter also listed prices for 5 sizes of the bottle from 7 ounces, all the way to a 1 gallon size. According to Fike, the Hirsutis was still being advertised in 1948.
Although no definite connection has been made between William Jay Barker and the Chevoux Tonique, odds are that it was his product. There were no other Barkers on Broadway during that period in any of the occupations associated with the hair business. Similarly, the "Hair Dresser" bottle was most likely another short-lived product of his. When Mary S. Barker registered the word "Hirsutis" and the symbols shown on the label as Trade Marks in 1881 (#22,645) she claimed that her husband had been making it since 1847. By the way, "Chevoux Tonique" just means Hair tonic in french.
Check this side label (view). I want to use this when I have a headache!
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