THE HABITABLE EARTH ORIGINALLY WOODED. 149 



and molten rock thrown out by Yesuvius soon become produc- 

 tive. Before the great eruption of 1631 even the interior of the 

 crater was covered with vegetation. George Sandys, who visited 

 Vesuvius in 1611, after it had reposed for several centuries 

 found the throat of the volcano at the bottom of the crater " al- 

 most choked with broken rocks and trees that are falne therein." 

 " Next to this," he continues, " the matter thrown up is ruddy, 

 light, and soft : more removed, blacke and ponderous : the utter- 

 most brow, that declineth like the seates in a theater, flourishing 

 with trees and excellent pasturage. The midst of the hiU is 

 shaded with chestnut trees, and others bearing sundry fruits." * 



I am convinced that forests would soon cover many parts of 

 the Arabian and African deserts, if man and domestic animals, 

 especially the goat and the camel, were banished from them. 

 The hard palate and tongue, and strong teeth and jaws, of this 

 latter quadniped enable him to break off and masticate tough and 

 thorny branches as large as the finger. He is particularly fond 

 of the smaller twigs, leaves and seed-pods of the sont and other 

 acacias, which, hke the American Robinia, thrive well on dry 

 and sandy soils, and he spares no tree the branches of which are 

 within his reach, except, if I remember rightly, the tamarisk that 

 produces manna. Young trees sprout plentifully around the 

 springs and along the winter watercourses of the desert, and 

 these are just the halting-stations of the caravans and their routes 

 of travel. In the shade of these trees, annual grasses and peren- 

 nial shrubs shoot up, but are mown down by the hungiy cattle of 

 the Bedouin as fast as they grow. A few years of undistm-bed 

 vegetation would suffice to cover such points with groves, and 

 these would gradually extend themselves over soils where now 



* A Relation of a Journey Begun An. Bom. 1610, lib. 4, p. 260, edition of 

 1615. The testimony of Sandys on this point is confirmed by that of Pighio, 

 Braccini, Magliocco, Salimbeni, and Nicola di Eubeo, all cited by Roth, Ber 

 Vesuv., p. 9. There is some uncertainty about the date of the last eruption 

 previous to the great one of 1631. Ashes, though not lava, appear to have 

 been thrown out about the year 1500, and some chroniclers have recorded an 

 eruption in the year 1306 ; but this seems to be an error for 1036, when a 

 great quantity of lava was ejected. In 1139, ashes were thrown out for many 

 days. I take these dates from the work of Roth just cited. 



