ture of snow and salt, and the 100 degrees was the temperature of melted tallow about to solidify.
It is, of course, inexpedient to attempt to chronicle in this volume every printed note on the thermometer, many of which did not bring their authors much fame, and did little to advance the instrument to perfection. But brief reference may be made to a "Dissertation" by Gabriel Philippe de la Hire, (Mémoires Acad. Science, Paris, 1706, p. 432), (son of Philippe just named) in which he mentions an instrument invented by Nugent in 1706, resembling that of Huyghens, and to a short article on the "Construction of Thermometers," by Elias Cammerarius in 1712 (Ephem. Acad. Nat. Curiosa, C. i and 2, p. 370), before we consider the eminent services to thermometry rendered by Fahrenheit.
In the year 1714, Christian Freiherr von Wolf, Chancellor of the University of Halle, and professor of mathematics and philosophy in the same, received a visit from Fahrenheit, a maker of philosophical apparatus in Amsterdam, who presented him with two thermometers made by himself, which agreed so perfectly in registering temperatures that the
