Convert from gnat's eye to toise

Unit Definition (gnat's eye)
The gnat's eye is an idiomatic "unit" of distance; it's common to hear that something is "as small as a gnat's eye". In fact, the eyes of typical gnats tend to have diameters similar in size to a hair's breadth: roughly 100-150 micrometers (0.10-0.15 millimeters).

Unit Definition (toise)
A linear measure used by the French in the old regime. A toise is equal to 76.71 English inches, 6.39 English feet or 1.9490 meters.