ANSWERS TO QUERIES. 119 



wise owl, in Anthony Froude's delightful story of the Cat's Pil- 

 grimage (itself a fine sample, by the way, of salt^ of the Attic 

 variety) : — Whether^ ifi the begUuiing of all things, did the owl first 

 arise fro)Ji the egg, or the egg fro?Ji the oivll The ovian problem 

 we must leave for the ornithologists to settle, or the owls, which- 

 ever are the wisest : with regard to the salt, the solution is pro- 

 bably quite simple. Sodium chloride is exceedingly abundant as an 

 element in our globe. The hydrogen flame, as every tyro in 

 chemistry knows, shows the yellow flame of sodium, if you only 

 shake the table, or walk across the room, thereby shaking a little 

 impalpable dust into the flame. The sea, as the great reservoir 

 into which all waters flow, contains the total result of their aeonic 

 work of solution, accomplished as they flow over the earth. Each 

 stream brings down some infinitesimal portion of salt, which is left 

 behind in the sea when the continually added water is removed by 

 evaporation. " Mony a little maks a mickle,'" and the salt which is 

 imperceptible, as an ordinary constituent of the soil, or of running 

 waters, is manifest enough in the ocean brine, and in its evapora- 

 ted deposit. It may be remarked, that rock-salt is a comparatively 

 rare mineral, since it depends for its accumulation on the excep- 

 tional conditions named, and a very short-lived one, because it is 

 no sooner deposited than the neighbouring streams begin to 

 dissolve it again, forming the brine springs, which always accom- 

 pany a salt deposit, and are often of nearly as much commercial 

 value as the rock-salt itself. 



2. — Gypsum (crystallised hydrous sulphate of lime). — Sea-water 

 contains a minute quantity of the substance of this mineral, 

 crystals of which may be observed, when sea-water is evaporated 

 under the microscope. It is consequently found associated with 

 rock-salt, as the natural evaporative product of sea-water. Its 

 chief source, however, is the very common mineral pyrites (iron 

 bisulphide). This, in the presence of air and moisture, gets a 

 part of its sulphur oxidised, and reacts on any neighbouring 

 deposit of limestone (carbonate of lime), so as to form gypsum. 



B. Lindsay, 



8.— Weather Notes. —The country people in the Isle of Man 

 say, it is a sign of storm when you see the fire reflected in the 

 glass of the window so clearly, that it looks as if the fire were 

 a real one situated out in the street. This is, I suppose, due to 

 the existence of a film of mist, condensed against the outside of 

 the window pane, when the air is very moist, this film converting 

 the glass into a mirror. 



