CLIMATE.— FLOEA. 53 



condition of prosperity, tlie salad del pueblo. During its prevalence the sun 

 remains clouded generally for a period of about eight daj's. 



At all times the rainfall is more copious in the southern provinces, where the 

 land is contracted between the Atlantic and Pacific inlets, and where the sun twice 

 crosses the zenith of the earth. Here the annual fall ranges from 80 to 120 inches, 

 gradually diminishing thence northwards to the regions beyond the tropic of 

 Cancer. Thus in Sonora the rains scarcely begin before the month of July, and 

 are frequently interrupted during the normal season. Those northern regions 

 especially which lie between the two main ranges have a very dry climate, the 

 moisture-bearing clouds being here intercepted by the slopes of the Sierra Madrés. 

 On these excessively arid plateaux a display of extremely vivid sparks is often 

 produced by the friction of two hard bodies. A continuous crepitation or crackling 

 sound is sometimes even heard escaping from all the rugosities of the rocky soil. 



As a whole the Mexican climate, if not one of the healthiest, is certainly one 

 of the most delightful in the world. The zone of " temperate lands " on both 

 oceanic slopes enjoys an "everlasting spring, " being exposed neither to severe 

 winters nor to intolerable summer heats ; in ever}^ glen flows a rippling stream ; 

 every human abode is embowered in a leafy vegetation, and here the native plants 

 are intermingled with those of Europe and Africa. Each traveller in his turn 

 describes the valley in which he has tarried longest as " the loveliest in the world," 

 that nowhere else the snowy crests or smoking volcanic cones rise in more im- 

 posing grandeur above the surrounding sea of verdure all carpeted with the 

 brightest flowers. In these enchanting regions there is still room for millions 

 and millions of human beings.* 



The Mexican flora is, so to say, a living illustration of its climate, for the 

 plants thrive or droop according to the varied conditions of temperature, aspect, 

 and moisture. From the character of the vegetation the botanist knows at once 

 whether the heat or cold is excessive, the oscillations of the thermometer mode- 

 rate or extreme, the rainfall abundant or slight. In these respects Mexico j^resents 

 the greatest contrasts, deserts and steppes alternating with scrub, and mighty 

 forests bound together in an inextricable tangle of creepers and undergrowths. 



In the northern regions the rocky Chihuahua and neighbouring provinces, 

 where rain seldom falls, have an extremely sparse vegetation, consisting of greyish 

 thorny plants with large hard leaves, a vegetation which adds little to the 



* Meteorological conditions of some Mexican stations taken in the direction from north to south : — 

 Stations. Latitude. height. ^^^Mean^^^.^_ KaJnMl. 



Monterey (1888) . 

 Mazatlan (six years) 

 Zacatecas (1888) . 

 San Luis Potosi (2 years 

 Leon (1888) . . 

 G-uanajuato (1888) 

 Guadalajara (6 years) 

 Mexico (12 years) 

 Colima (15 years) 

 Puebla (2 years) . 

 Oaxaca (1879) . 



25° 40' 1,636 70- F. 137 



23^ 11' 150 76° i,9 



22° 47' 8,100 58° .19 



22° 05' 6,230 62" 16 



21° 7' 5,920 65° 35 



21° 1' 6,645 63° 33 



20° 41' 5,180 72° 34 



19° 26' 7,400 60° 30 



19° 12' 1,655 78° 42 



19° 7,110 60° 39 



17° 3' 5,108 67° 38 



