Creator
Alexander G. McAdie
Recipient
John Muir
Preview
Transcription
2think the clouds resembles humans. They are just as restless, seem never quite at ease and often surge hither and thither like an excited populace. Again, some rise steadily and some fall. Some are joys forever to the eyes below, beholding them; some are but confused and uncertain wanderers; and some, when most is expected of them, fade away, casting only a shadow, when a thirsty land hoped for rain.The water vapor condenses,it is thought, only when minute nucleis are present to serve as centers of condensation. It is claimed that in a perfectly dust-free air no drops will form; but light may ionize air that we would otherwise consider dust-proof, and the necessary nuclei [Illegible] present. Out in the open probably there is never a time that cloud particles could not form provided the supply of water-vapor is present. The average size of a rain drop is from two to four millimeters. The largest drops are about seven mm. Fine drops fall at varying rates and drops take on various sizes with facility. With very fine drops the viscous resistance of the air prevents falling. Professor Lenard of Kiel, about five years ago, published a paper on his experiments with rain drops. He produced vertical currents of air which could be regulated and measured, and drops of various sizes falling04734
Location
San Francisco
Date Original
1910 Mar 19
Source
Original letter dimensions: 25 x 20 cm.
Resource Identifier
muir19_0257-let.tif
File Identifier
Reel 19, Image 0257
Copyright Status
Copyright status unknown
Copyright Statement
Some letters written to John Muir may be protected by the U.S. Copyright Law (Title 17, U.S.C.). Transmission or reproduction of materials protected by copyright beyond that allowed by fair use requires the written permission of the copyright owners. Responsibility for any use rests exclusively with the user.
Owning Institution
University of the Pacific Library Holt-Atherton Special Collections. Please contact this institution directly to obtain copies of the images or permission to publish or use them beyond educational purposes.
Page Number
Page 2
Keywords
John Muir, correspondence, letters, author, writing, naturalist, California, correspondent, mail, message, post, exchange of letters, missive, notes, epistle
