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is to the Hoclistetters that ^^'e are most indebted for information 

 ^n the subject. It was with mingled feelings^ of satisfaction and 

 aisappointment that the writer discovered that all his main results 

 •were m close agreement with those of the German investigators 

 and of their later fellow-workers in this field. 



The great volcanic cone of Pico, 7613 ft. in altitude, is by far 

 the highest mountain in the Azores, none of the other islands 

 attaining half its height. There are eight other islands in the 

 group, and it is very remarkable that the three largest and most 

 elevated of them have practically the same elevation, San Miguel 

 3570 ft., Terceira 3500 ft., and San Jorge 3498 ft., whilst the two 

 islands next in size, Fayal and Flores, are not much lower, their 

 heights being 3351 and 3087 ft. respectively. This is a physical 

 feature of importance, since Pico loses the advantage of its much 

 igreater elevation on account of the predominance of lava and 

 binders in its upper portion; and for purposes of comparison as 

 concerning suitable soil-conditions foi' vegetation we may regard 

 only its lower 4000 or 4500 ft. Even on the island of Pico the 

 same rule applies, since with the exception of the peak none of 

 the other mountains exceed 3500 ft. in height. It is true that 

 Pico Topo behind Lagens is credited in the Admiralty chart and 

 in the accompanjang Sailing Directions with an altitude of 

 5357 ft. ; but there is an error here, the true elevation as the 

 uuthor ascertained being about 3300 ft. 



From what has been just said we should be safe in assuming 

 that the soil-conditions for forest-growth in the Azores cease 

 usually at altitudes between 3000 and 4000 ft. It would seem 

 from the early accounts of Madeira that the original forests must 

 have extended nearly to the summit of the island, and we will 

 take their average limits as between 5000 and 6000 ft. In the 

 Canaries, as illustrated by Teneriffe, this limit would be generally 

 •about 7000 ft. After applying to these values for the three 

 Macaronesian groups the correction for the difference in latitude 

 and for the associated differences in climate we should expect to 

 find in the Azores the Canarian forest vegetation of between 

 2000 and 5000 ft., or in other words the evergreen shrubs and 

 trees of the Laurel belt. We could scarcely look for more, since 

 •the higher Pine belt of Teneriffe could not exist on the lava and 

 cinders of the higher levels of Pico, whilst the lower coast belt 

 with all its strange plants would be unrepresented for lack of the 

 wrarm climatic conditions. The significance of this inference will 

 hecome apparent in a later page; but it is by no means a. novel 

 one. It will be found in the pages of Seubert, Hochstetter, and 

 llorelet, and is implied in the writings of Hooker. 



The characteristic appearance of the great cone of Pico is that 

 of a mountain rising with easy slopes for its lower two-thirds and 

 then ascending precipitously to the summit. Except on the 

 southern side it rises gently up to between 2000 and 2500 ft. ; 

 after which there is a steeper gradient to between 4500 and 

 5000 ft. ; and then it ascends rapidly to the top. The impression 





formed at a distance that the lower two-thirds are vegetated, 

 -whilst the lava slopes of the upper third are barren, is verified 

 5only in a relative sense when the observer ascends the mountain. 



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