Filed november 19, 1891, and registered june 14, 1892, it seems that the musical instrument patented by William Carter, Albion, New York, was the first modern metal nose flute [US477167]. The design is rudimentary, but already rather compact and hand-free, with a nose-cap, a tube sucked by the operator and a rubber passing though a little conduit at the end of its nose and ended by some kind of temple tips to hook the ears.
« This invention consists in an instrument of novel character and which may appropriately be called a «nasalette», inasmuch as it is a means designed to be used in the production of sound by the passage of air from or blowing through the nose and regulating and varying the sound so produced to obtain any desired tone by the player working or changing the position of his tongue, substantially as hereinafter described, and more particularly pointed out in the claims. »
I do not know if a prototype was realised, but I doubt the configuration shown on the templates (Fig. 1 & 2) would have produced a good result. In my opinion, the air expired from the nostrils would hardly reach the tapered duct and in no case with a sufficient flow to activate the whistle. However, with minor modifications to the nose-cap, the whole system would perfectly be efficient.
Apparently, this is the only patent the pioneer left to us. The Carter's nasalette was only referenced by another patent, in 2002, regarding a curious theatrical dental apparatus with ornament [US6450814].