96 OUR FARM CROPS. 



to acknowledge its efficacy as a valuable therapeutic agent 

 in certain diseased conditions of the surface, though our 

 ladies hardly admit it as a general or necessary constituent 

 of their toilette. 



Of all our cultivated grains, barley has the greatest 

 range of cultivation ; it comes to maturity in almost every 

 climate in the world, and thus is grown in the torrid, as 

 well as in the brief but hot summers of those countries 

 verging on the frigid zones. It is largely grown and used 

 as a bread-corn in those cold climates where wheat cannot 

 be successfully cultivated; and it is equally grown and 

 used as a food for horses and cattle in the arid countries 

 of the East, whose dry and hot climates render the culti- 

 vation of the oat impracticable. In the northern parts of 

 Sweden and Norway, in Lapland and Siberia, it is more 

 cultivated' than either of the other cereals, chiefly on 

 account of its quicker growth and earlier maturity, it not 

 requiring to be more than seven or eight weeks in the 

 ground, between seed-time and harvest. Linnaeus found 

 barley growing as a crop at Lulloea in Lapland, lat. 67 20' 

 N., where it was sown on 'May 31, and was harvested on 

 July 28, having reached its maturity in fifty-eight days. 

 If we follow its cultivation towards its northern limits 

 in Europe, we see how well it illustrates that beautiful 

 arrangement conceived by Humboldt, and worked out by 

 himself, Dove, and others, that, vegetable life being influ- 

 enced mainly by temperature, cultivation is consequently 

 determined by the zones of temperature, and not by zones 

 of latitude or distance from the equator. These zones of 

 temperature were arranged for the purpose of marking or 

 joining together all those places where the same annual 

 mean temperature exists, and are then termed isothermal 

 zones; and also of marking or joining together all those 

 places where the same summer mean temperature exists, 

 in which case they are distinguished from the others by 



