When the light bulb was cheaper and better, we ditched kerosene.
A single bulb dangled from the ceiling, lighting up a wide area but not the entire space.
It consists of a glass bulb, in which there is a loop of fine wire, and to the bulb is attached a U-tube in which there is some liquid.
The principle is to have a constriction in the tube above the bulb so proportioned that when the instrument is upright it acts in every way as an ordinary mercurial thermometer, but when it is inverted the thread of mercury breaks at the constriction, and the portion above the point runs down the now reversed tube and remains there as a measure of the temperature at the moment of turning over.
The species are numerous, and are distinguished one from another by the scales of the bulb being woolly or smooth on the inner surface, by the character of the flower-stalks, by the filaments being hairy or otherwise, and by other characters.