Curiosities of Science. 157 



calms and baffling winds, it is a region noted for its rains and 

 clouds, which make it one of the most oppressive and disagree- 

 able places at sea. The emigrant ships from Europe for Aus- 

 tralia have to cross it. They are often baffled in it for two or 

 three weeks ; then the children and the passengers who are of 

 delicate health suffer most. It is a frightful graveyard on the 

 wayside to that golden land. 



BEAUTY OF THE DEW-DROP. 



The Dew-drop is familiar to every one from earliest infancy. 

 Resting in luminous beads on the down of leaves, or pendent 

 from the finest blades of grass, or threaded upon the floating 

 lines of the gossamer, its " orient pearl" varies in size from 

 the diameter of a small pea to the most minute atom that can 

 be imagined to exist. Each of these, like the rain-drops, has 

 the properties of reflecting and refracting light ; hence, from so 

 many minute prisms, the unfolded rays of the sun are sent up 

 to the eye in colours of brilliancy similar to those of the rain- 

 bow. When the sunbeams traverse horizontally a very thickly- 

 bedewed grass-plot, these colours arrange themselves so as to 

 form an iris, or dew-bow ; and if we select any one of these 

 drops for observation, and steadily regard it while we gradually 

 change our position, we shall find the prismatic colours follow 

 each other in their regular order. Wells. 



FALL OF DEW IN ONE YEAK. 



The annual average quantity of Dew deposited in this coun- 

 try is estimated at a depth of about five inches, being about 

 one-seventh of the mean quantity of moisture supposed to be 

 received from the atmosphere all over Great Britain in the 

 year ; or about 22,161,337,355 tons, taking the ton at 252 im- 

 perial gallons. Wells. 



GRADUATED SUPPLY OF DEW TO VEGETATION. 



Each of the different grasses draws from the atmosphere 

 during the night a supply of dew to recruit its energies de- 

 pendent upon its form and peculiar radiating power. Every 

 flower has a power of radiation of its own, subject to changes 

 during the day and night, and the deposition of moisture on 

 it is regulated by the peculiar law which this radiating power 

 obeys ; and this power will be influenced by the aspect which 

 the flower presents to the sky, unfolding to the contemplative 

 mind the most beautiful example of creative wisdom.* 



* By far the most complete set of experiments on the Radiation of Heat from 

 the Earth's Surface at Night which have been published since Dr. Wells's Me- 

 moir On Dew, are those of Mr. Glaisher, F.R.S., f kilos. Trans, for 1847. 



