Littell's Living Age/Volume 136/Issue 1751/Miscellany

Determination of the heights or clouds. — Mr. Alexander Ringwood, of Adelaide, has sent home a short paper on this subject, which appears to have been privately printed. He proposes to carry out the observations with a small simple altazimuth instrument. The principle is intelligible enough. The sun's altitude being known, and the edges of the projections of cloud shadows being parallel to the sun's rays: if we have a map of the country round the station, and mark on it the spots where the sun‘s rays strike through clouds, or where the shadows of clouds fall, the determination of the height of the cloud stratum is effected by plane trigonometry, if we observe the altitude of the precise points in the cloud.