What was advertised in a colonial American newspaper 250 years ago today?

“This valuable tincture … sold … at Mrs. CROSSWALL’S in Thames-street[,] Newport.”
In the summer of 1769, Mr. Hamilton, a “Surgeon Dentist and Operator for the teeth, from LONDON,” offered his services to residents of New York. He also advertised a tincture for curing toothaches that he made available beyond New York and its hinterlands. In marketing that remedy, Hamilton placed advertisements in multiple newspapers in New York as well as newspapers published in other cities. In those other locations, the advertisements specified local agents who distributed the tincture on Hamilton’s behalf. The Pennsylvania Gazette, for instance, ran an advertisement identical to those that appeared in newspapers in New York except for the addition of local agents in Lancaster and Philadelphia. It made sense for Hamilton to commence his attempt to enlarge his market with the Pennsylvania Gazette. Printed in Philadelphia, the largest city in the colonies, the Pennsylvania Gazette had an extensive circulation as a regional newspaper whose “local” readers included colonists throughout Pennsylvania as well as Delaware, Maryland, New Jersey, and beyond.
Hamilton, however, did not confine his efforts to newspapers published in New York and Pennsylvania. He also inserted his advertisement in the Newport Mercury, hoping to attract customers in Rhode Island and other parts of New England. That advertisement featured identical copy except for the inclusion of a local agent who sold Hamilton’s tincture for curing toothaches. Hamilton instructed interested parties to acquire it “at Mrs. CROSSWALL’S in Thames-street[,] Newport.” The advertisement did not specify whether Crosswall or one of her boarders served as Hamilton’s local agent, nor did the advertisement in the Pennsylvania Gazette specify whether it named local agents in Lancaster and Philadelphia or their landlords.
If these advertisements did name the local agents, Hamilton worked with women in Newport and Philadelphia. Although lacking titles like “Surgeon Dentists and Operator for the teeth,” these women exercised medical authority as they consulted with clients in the process of distributing the tincture and, especially, in making determinations about the “No CURE No PAY” guarantee that Hamilton included in every advertisement. He did not limit that guarantee to customers in New York who purchased the tincture directly from him. Instead, he extended it to customers who acquired the tincture in Lancaster, Newport, and Philadelphia, transferring responsibility to local agents for making assessments about the veracity of claims made by anyone who claimed that the tincture had not alleviated their pain.
Hamilton’s endeavor to enlarge the market for his tincture demanded attention to detail in distributing the product and “particular directions for using it.” He also had to cultivate relationships of trust with his local agents who represented him to distant customers. This was especially important since he depended on them exercising medical authority in their interactions with local clients. Hamilton sought to create a widely recognized brand, not unlike many patent medicines familiar to consumers throughout the British Atlantic world, but doing so required cooperation with associates and agents in faraway places.