352 GRISCOM ON METEOROLOGICAL OBSERVATIONS. 



as susceptible of much precision, and rarely defective in its results. It 

 is that which regards changes announced by prognostics drawn from 

 animals, plants, and every thing which indicates changes of atmos- 

 phere.* A good journalist should not hesitate to insert any remarkable 

 presage of this nature. The domestic fowl, the swallow, the hog, the 

 horse, and other animals, may thus contribute to the extension of useful 

 science. Plants which fold their petals and leaves in the night, and 

 usually open in the day, are delicately affected by incipient changes in 

 the air. The Calendula Pluvialis derives its name from this property, 

 which is said to be very decisive. 



An unusual transparency of atmosphere, in which distant objects 

 become visible by refraction, and which favours the propagation of 

 sound in an uncommon degree; the perpendicular ascent of smoke, and 

 a more than usual stillness and serenity of nature, are likewise to be 

 taken into the account. 



But, among the various objects which claim the attention of the 

 meteorological observer, he must, by no means, omit those from which 

 his science, in its strict and literal acceptation, derives its name. The 

 phenomena of meteors constitute an interesting part of natural history. 

 Hence every remarkable appearance of fire balls, shooting stars, ignes 

 fatui, together with the aurora borealis, zodiacal light, halos, parhelia, 

 para selena, lunar rainbows, and other analogous occurrences, ought to 

 be diligently observed, and carefully noted. 



Finally, we recommend, as a very useful addition to the series of 

 facts brought into view, that the period of the first appearance of early 

 flowers, in open and exposed situations, in the spring of every year, 

 designated by their botanical names, be noted, with as much precision 



• Vide Rozier's Cour Complet d'Agriculture, Art. Presage. 



