original and intact antique dug blue aqua 'midget' mason jar manufactured by the consolidated fruit company. the heavily irridized vibrant blue jar is finished with a ground lip, which appears as if smoothed off on a grinding wheel, leaving a somewhat rough surface. the finish retains a small remnant of a zinc lid. the front body is embossed "mason's" above the consolidated fruit company's open-lined monogram, and below "patent / nov. 30 / 1858". this jar was salvaged from an area south of downtown chicago, in a landfill that yielded dozens of mid to late nineteenth century bottles. crudities are typical of its age and date of manufacture, and debris or irridization are typical of being dug. this “mason’s / patent / nov 30th / 1858” phrase was originally embossed on countless glass fruit jars (canning jars) ranging in age from circa 1858 to the early 1920s. john landis mason was awarded patent #22186, issued on november 30, 1858 by the u.s. patent & trademark office (actually the patent was termed an “improvement in screw-neck bottles”), for his invention concerning the process of creating a threaded screw-type closure on bottles and jars. similar screw-threading had appeared on bottles, but the process of forming the upper lip area of the container (so that it was smooth, even, and sturdy enough for a lid of standard size to be screwed on) was difficult and expensive to properly fabricate with satisfactory results. his improvement revolutionized home canning in the united states. the very first jars with this patent date embossing are believed to have been made at the “crowleytown” glass works (more accurately the atlantic glass works), located in washington township, new jersey. another firm which was producing the jars early on was the consolidated fruit jar company, perhaps making them as early as 1859 or 1860. questions remain on exactly which companies made these jars during the early years, since the 1858 patent evidently lasted 13 years (or 20 years, counting a patent reissue), and ostensibly during that time period no one was allowed to produce the jars because of patent infringement issues unless they were granted permission by mason, or the licensed holder of the patent. throughout the next 60-odd years, production of jars with the "nov. 30, 1858" embossing continued at a high rate. the phrase was soon considered an important marketing device, adding to the perception of quality and reliability of the container to the average consumer, and, at least by 1879 (21 years after the patent was issued), it is very likely that nearly every glass bottle factory was producing their own version. the 1880s and 1890s likely saw the peak of popularity of these jars. a considerable percentage have a mold number or letter on the base.