, in the Franklin Institute.
In an advertizing pamphlet published ca.1879 by the MacKinnon Pen Co., they mentioned that their pen was “hailed by The Scientific American in an exceedingly complimentary editorial”, which “gave the key-note to the press throughout the country, and the name of MacKinnon was heralded far and near”. The pamphlet also described the A. T. Cross stylo as “a delusion and a snare”, and that Cross was “wilfully or ignorantly deceiving the public” because they did not have the MacKinnon “weighted needle” and the “circle of iridium”. It also says that the pen “received a practical test for over six months in the hands of the able professors of [the Franklin Institute]”, which issued a report dated May 7, 1879.
The Committee on the Sciences and Arts constituted by the Franklin Institute of Pennsylvania, to whom the “MacKinnon Fountain Pen” was referred for examination, reported that, “This is one of the latest forms of pocket or desk pen for miscellaneous use. It resembles in general outline other contrivances for the same end. Its main body or handle is a hollow tube of vulcanized rubber. This tube is the ink reservoir, and is filled by an elastic syringe [eye dropper], which accompanies the pen. The point of the pen is actually a ring of iridium attached to a gold tube surrounding a delicate shaft of the same metal which protrudes through the tube in the manner of the famed Addison lead pencil of half a century since. The pressure of the writer upon the paper opens the supply aperture of the ink reservoir, which closes immediately on lifting the pen, thus preventing evaporation and other means of waste. It is at once tasteful and useful, and for the service rendered is not costly”.
And finally, in The Journal of the Franklin Institute, June 1879, p.432, there was a report of the proceedings at their May 21, 1879 meeting, which mentioned that one of the items on their agenda was “the MacKinnon Fountain Pen, the iridium ring of which was exhibited with the micromegascope on the screen”. The micro-megascope is described in The Journal of the Quekett Microscopical Club, 1883, p.171. There’s also a description in The Microscope and its Revelations, v.1, p.108, but no illustration. A picture of a similar demonstrating microscope on p.101 gives an idea of what it might have looked like, except the lamp-and-slide are replaced by the illuminated-object-and-mirror. Its purpose was to demonstrate small objects to an audience, or large group of spectators, and the microscope was converted into a telescope and a projector.