Newburyport, MA: Hale & Company, 1866. A circular filled with testimonials for the Aerifying Egg Beater patented in 1866 and produced by Hale & Company in Newburyport, MA. The first page has a wonderful woodcut of the manufacturing building of Hale & Co., along with a description of of the item. The beater uses a "system of aerifying, as it fills the eggs with minutely divided and finely subdivided particles or globules of pure air." The interior of the circular lists numerous testimonials. On the back of the circular is draft of a letter written by J. Hale Jr, owner of Hale & Company, to a William Pebt, Esq. regarding the possible sale of a mailing list of approximately 5,000 names and address. The letter is dated January 31, 1870, and when Hale & Co. had been bought out by another company. Single fold circular. Measures 10 3/4" x 8" (folded), 16" x 1 0 3/4" (unfolded). Age toning and soiling. Crease marks and minor separation at the fold.