SCIENCE, INVENTION, DISCOVERY. 



309 



Temperature. As winds are but masses of 

 air set in motion by the unequal heating, the 

 winds of any given place depend primarily 

 upon the temperature, though not necessarily 

 upon the temperature of that place. As the 

 air is heated in the tropical parts of the earth 

 by the sun, it rises, and colder air flows in 

 from the polar regions to take its place ; hence 

 the primary currents, which are modified in 

 various ways by other causes. 



Rotation of the Earth. The winds are turned 

 out of their course by the rot'ation of the earth 

 in the same manner as the- ocean currents. 



Land and Water The land becomes warmer 

 during the day than the sea, and, the air rising, 

 a cooler air flows in from the sea. At night 

 the land parts with its heat more rapidly than 

 the water and becomes cooler ; then the wind 

 sets the other way. Hence we have the land 

 and sea breezes. 



Elevation of the Land. Mountains, as has 

 already been stated, shelter places from winds. 

 Some of the great plains are subject to almost 

 constant winds. 



In regard to moisture, the climate of a place 

 depends upon : 



Prevailing Wind. If a wind blows from 

 large bodies of water in a warm region it will 

 be laden with moisture which will be likely 

 to be precipitated on reaching a colder country. 



Mountains. The contact of a moisture- 

 laden wind with the cold sides of mountains 

 will cause a precipitation of its moisture, and 

 the regions beyond the mountains will not 

 receive it. 



Forests, by shading the earth, keep its surface 

 cool, and this tends to condense the moisture. 



Cultivation of the Soil, causing it to absorb 

 moisture from the atmosphere, and by capil- 

 lary attraction in dry weather bring up mois- 

 ture from below to the surface. 



Temperature. Increased heat causes greater 

 evaporation, and hence more moisture in the 

 atmosphere. More rain falls within the tropics 

 than in the temperate or polar regions. 



Land and Water. - More rain falls on the 

 coasts of a country than in the interior, be- 

 cause the winds are more moist. More rain 

 falls in the northern hemisphere than in the 

 southern, because there is a greater diversity of 

 land and water, the evaporation coming mainly 

 from the ocean, and the condensation from the 

 diversified land surface. 



Isothermal lines are lines connecting places 

 that have the same mean temperature. 



There is a line or limit of elevation, above 

 which the surface is covered with perpetual 

 snow; this is called the snow-line. 



Coaches. Covered carriages appear to 

 have been used by the old Romans. In the 



year 1588, Duke Julius of Brunswick published 

 an act against riding in coaches. Philip II. 

 of Pomerania- Stettin published a similar doc- 

 ument in 1608. Coaches appear to have been 

 used in France very early. An ordinance of 

 Philip the Fair, issued in 1294, for suppressing 

 luxury, forbids citizens' wives to ride in 

 coaches. Coaches were first used in England 

 in 1565, the firs't being that made for the Earl 

 of Rutland. In 1601 an act was passed to 

 prevent men riding in coaches, on the score 

 of its effeminacy. Coaches began to be com- 

 mon in 1605, and were petitioned : against by 

 the saddlers and other. Hackney coaches in- 

 troduced in 1634. In 1661, a stage coach 

 was two days going from London to Oxford, 

 and the "flying coach " was thirteen hours, 

 even in summer weather, when the roads were 

 at their best. 



Coffins. Athenian heroes were buried in 

 coffins of the cedar tree, owing to its aromatic 

 and incorruptible qualities. Coffins of marble 

 and stone were used by the Romans. Alex- 

 ander is said to have been buried in one of 

 gold ; and glass coffins have been found in 

 England. The earliest record of wooden 

 coffins among the English speaking people is 

 that of the burial of King Arthur in an entire 

 trunk of oak, hollowed, A. D. 542. The 

 patent coffins were invented in 1796. 



Coin. Silver was first coined by Phidon, 

 King of Argos, 869 B. C. In Rome, silver 

 money was first coined 269 B. C. Gold and 

 silver coins first used in the East. Coin first 

 used in Britain 25 B. C., and in Scotland not 

 until 248 years later. In 1101, round coins 

 were first used in England. Silver halfpence 

 and farthings were coined in the reign of John, 

 and pence were the largest current coins. Gold 

 was first coined in England in 1087 ; in Bohe- 

 mia, in 1301. In 1531, groats and half-groats 

 were the largest silver coin in England. Gold 

 was first coined in Venice in 1346. Shillings 

 were first coined in England in 1068. Crowns 

 and half-crowns were first coined in 1551. 

 Henry III. introduced copper money into 

 France in 1580. Copper money introduced 

 into England by James I. in 1620. The proc- 

 ess of milling coin introduced in 1662. The 

 mint of the United States of America was es- 

 tablished in 1793. 



Comets. It has been lately suggested 

 that there is a great degree of affinity between 

 comets and meteors in fact, that a comet is 

 merely an aggregation of meteors. Comets 

 have been supposed to be bodies of burning 

 gas. Their mass is very great, and their bril- 

 liant tails are many millions of miles in 

 extent. In their orbits, they differ greatly 

 from the planetar. While the latter are direct 



