163 THE FARMER AT HOME. 



with larger bodies. To inquire, therefore, into the nature of fluids, 

 is to consider what appearances a collection of very small round 

 bodies, subject to these laws, will exhibit under different circum 

 stances. 



FLYING. The progressive motion of a bird or other winged 

 animal in the air. The parts of birds chiefly concerned in flying are 

 the wings and the tail ; by the former, the bird sustains and wafts 

 himself along ; and, by the latter, he is assisted in ascending and de- 

 scending, to keep his body poised and upright, and to obviate the vas- 

 cillations thereof. It is by the largeness and strength of the pectoral 

 muscles that birds are so well disposed for quick, strong, and continual 

 flying. These muscles, which in men are scarcely a seventieth part 

 of the muscles of the body, in birds, exceed and outweigh all the other 

 muscles taken together. 



FOG, or MIST. A meteor consisting of gross vapors, floating 

 near the surface of the earth. Mists, according to Lord Bacon, are 

 imperfect condensations of the air, consisting of a large proportion 

 of the air, and a small one of the aqueous vapor ; and these happen 

 in the winter, about the change of the weather, from frost to thaw, 

 or from thaw to frost ; but in the summer and the spring, from the 

 expansion of the dew. 



If the vapors, which are raised plentifully from the earth and 

 waters, either by the solar or subterraneous heat, do, at their first 

 entrance into the atmosphere, meet with cold enough to condense 

 them to a considerable degree, their specific gravity is by that means 

 increased ; and so they will be stopped from ascending, and return 

 back, either in form of dew, or drizzling rain, or remain suspended 

 some time, in the form of fog. Vapors may be seen on the high 

 grounds as well as the low, but more especially about marshy places. 

 They are easily dissipated by the wind, as also by the heat of the sun. 

 They continue longest in the lowest grounds, because these places 

 contain most moisture, arid are least exposed to the action of the 

 wind. 



Hence we may easily conceive, that fogs are only low clouds, or 

 clouds in the lowest region of the air ; as clouds are no other than 

 fogs raised on high. When fogs stink, then the vapors are mixed 

 with sulphureous exhalations, of which they smell. Objects viewed 

 through fogs appear larger, and more remote, than through the com- 

 mon air. Boyle observes, that upon the coast of Coromandel, and 

 the most maritime parts of the East Indies, there are, notwithstand- 

 ing the heat of the climate, annual fogs so thick, as to occasion those 

 of other nations who reside there, and even the more tender part of 

 the natives, to keep their houses close shut up. 



FOOD. Many persons are unaware of the great difference of 

 nutritious matter contained in different articles of food in daily use. 

 One might distend his stomach like a bladder, upon turnips, and yet 



