M. E. Gillespie, of Boston, Mass., registered a Trademark for "Hair Shampoos and Tonics" sometime after the turn of the century, but I lost the date from the original (TM #90,530). The pamphlet I purchased says that at some point the Proprietor of the company was P. A. Houghton. At that time it was also located in Winthrop Highlands, Mass. The monogram for the product was P.A.G. I would suggest that possibly P.A. Gillespie was a woman who later became P.A. Houghton.