This log and clapboard building was built c. 1810 by John Slagle, who sold it to Josiah Massie in 1815. Mr. Massie could lay claim to several "hatter's shops" around downtown Winchester, including one at the current site of another Revolving Fund property, the Huntsberry Building (157 N. Loudoun,) but the Boscawen location may be the last extant building he used for his shop, and so it has been given the affectionate, if somewhat disingenous, name of "Josiah Massie's Hatter Shop," as if there were only one in Winchester.

William Greenway Russell recalls the building being "much improved" by a subsequent owner, William Diffender, who owned the property from 1838-1863. He is most likely referring to the large additions to the rear of the property, noted as a kitchen wing in PHW's survey of the building. The building continued to house commercial enterprises until it was purchased by the Revolving Fund in 1978. This property features a unique covenant due to the building's commercial nature: An optional storefront design featuring an alternate three door and two large-paned window configuration, which was the design at the building's purchase by PHW in order to accommodate two shops on the first floor.