ASTRONOMY AND METEOROLOGY. 371 



certainty -with winch anything is arrived at on this subject, like all 

 other parts of natural science, depends upon the knowledge acquired 

 of those things with which nature has most intimately connected it. 



Without indulging in any comment, I Avill state a few particulars in 

 regard to the different indicators with which nature has supplied us. 



When a pair of migratory birds have arrived in the Spring, they 

 immediately prepare to build their nest, making a careful reconnoisance 

 of the place, and observing the character of the season that is coming. 

 If it be a windy one, they thatch the straw and leaves on the inside of 

 the nest, between the twigs and the lining ; and if it be very windy, 

 they get pliant twigs and bind the nest firmly to the limb, securing all 

 the small twigs with their salivas. If they fear the approach of a 

 rainy season, they build their nests so as to be sheltered from the 

 weather. But if a pleasant one, they build in the fair open place, 

 without taking any of those extra precautions. In recording these 

 facts, we have kept duly registered the name of the bird - - the time 

 of arrival in Spring the commencement of nesting the materials of 

 nest, and its position the commencement of laying number of eggs 

 in each\est commencement of incubation appearances of young 

 deparrWe in Autumn. 



But it istmr insects and smaller animals which furnish us with the 

 best means of determining the weather. 



We will now take the Snails and show the various phenomena they 

 present". These animals do not drink, but imbibe moisture in their 

 bodies during a rain. At regular periods after the rain they exude 

 this moisture from their bodies. AVe will take, for example, the Helix 

 alternata. The first fluid exuded is the pure liquid. When this is 

 exhausted, it then changes to a light red, then deep red, then yellow, 

 and lastly to a dark drown. The Helix is very careful not to exude 

 more of its moisture than is necessary. It might exude it all at once, 

 but this is not in conformity to its general character, as this would 

 prove too great an exertion. The Helix alternata is never seen 

 abroad, except before a rain, when we find it ascending the bark of 

 trees and getting on the leaves. The Helices arborea, indentata, 

 ruderati, and ?ninuta, are also seen ascending the stems of plants two 

 days before a rain. The Helices clausa, ligera, Pennsylvaniea, and 

 elevata, generally begin to crawl about two days before the rain will 

 descend. They are seen ascending the stems of plants. If it be a 

 long and hard rain, they get on the sheltered side of the leaf, but if a 

 short one, they get on the outside. The luccinea have also the same 

 habits, differing only in color of animals, as before the rain it is of a 



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yellow color, while after it is a blue. The Helices solitaria, zaleta, 

 albolabris, and thyroideus, not only show signs by means of exuding 

 fluids, but by means of pores and protuberances. Before a rain, the 

 bodies of zaleta and H. thyroideus have large tubercles rising from 

 them. 



These tubercles commence showing themselves ten days previous to 

 the fall of rain they indicate ; at the end of each of these tubercles is 

 a pore. At the time of the fall of the rain, these tubercles with their 



