OF FOREST-TREES. 265 



Keep your newly-sown seeds continually fresh, and in tlie shade, (as CHAP. V. 

 much as may be,) till they peep. 



All curious seeds and plants are diligently to be weeded, till they are 

 strong enough to over-drop or suppress them : and you shall carefully 

 hoe, half-dig, and stir up the earth about their roots during the first 

 three years, especially in the vernal and autumnal equinoxes : this work 

 should be done in a moist season for the first year, to prevent the dust 

 from suffocating the tender buds ; but afterwards in the more dry 

 weather. 



Plants raised from seed should be thinned where they come up too 

 thick ; and none so fit to be transplanted into hedge-rows as those you 

 thus draw, especially where ground is precious. 



of Florida and Palestine, the Cape of Good Hope, and Chili, in South America, places 

 which exactly correspond in latitude ; the two former situated in the northern hemisphere ; 

 the latter in the southern. What has been affirmed of latitude, may likewise be asserted 

 of places that are situated upon the same meridian. Thus the North Cape, Rome, Upsal, 

 the Cape of Good Hope, agree in longitude, yet produce plants that are totally different. 

 The aptitude or disposition of plants to grow in certain climates, and not in others, seems 

 to depend not so much upon longitude and latitude, as upon the elevation of the soil, 

 or difference of temperature in such climates. From this cause proceeds the difference 

 which is generally found to obtain betwixt the plants of the torrid, and those of the tem- 

 perate and frigid zones. For when in the torrid zone we find the mountains, which, by 

 their elevation, have acquired a temperature similar to that of the temperate or frigid 

 zones, we always discover on such mountains the same, or, at least, a part of the same 

 plants. Thus the plants on the mountains of Lapland, of Switzerland, Greenland, Siberia, 

 Wales, the Pyreneans, Olympus, Ararat, and Brazil, though placed at such immense dis- 

 tances from each other, are nearly the same. As at a certain depth, the temperature of 

 water is found to be nearly the same in all climates, so the greatest part of aquatic plants 

 are common to the torrid, temperate, and frigid zones. Thus the Water-lily, Aldrovanda, 

 Sun-dew, Arrow-head, Water-milfoil, and many other aquatics, are equally natives of Europe 

 and the Indies. 



It is remarked by many writers, that the climate of modern Europe is much warmer than 

 that of the ancient ; and as a proof of its being so, we need only compare the testimonies 

 of the most authentic ancient writers with our own observations and experience. The 

 Abbe du Bos observes upon the climate of Italy, that it is warmer at present than in 

 ancient times. He says, " The annals of Rome tell us, that in the year 480, ab. U. C, 

 " the winter was so severe, that it destroyed the trees. The Tyber froze at Rome, and 

 " the ground was covered with snow forty-five days. When Juvenal describes a super* 



