On the use of the tasimeter for measuring the heat of the stars and of the Sun's corona

Dear Sir: The instrument which I used at Rawlins, Wyoming, during the solar eclipse of July 29,1878, for the purpose of measuring tile heat of the 8un's corona, was devised by me a short time only before that event; and the time was insufficient to allow me to give it as thorough a test as was desirable to ascertain its full capabilities and characteristics. This instrument I have named the tasimeter, from the Greek words ramr;, extemlion, and /lcrpo)), measure, because primarily the effect is to measnre extension of anv kind. The form of instrument which I Llsed is shown in the ;nnexed wood-cut (fig. 1.)