PE0DI3CED BY MAN. 825 



Admiral Smyth (p. 1 7 of his ' Memoir of Sicily and its Islands,' 1824), 

 that they ' form impenetrable palisades for fortifications, and in the 

 plains present very serious obstructions to the operations of cavalry.' 

 My third map, with the distribution of the vine after Schouw, 

 should be compared with my picture from Kaempfer's ' Amoenitates 

 Exoticae,' Ease. iv. p. 711, 171 2, of what he calls, p. 714, the 

 Messis dactyl'ifera^ the date-harvest of Persia, and speaks of as being- 

 ' lusus magis quam labores.' The distributional limits of the 

 'fruitful' vine and the 'fruiting' date-palm now, as of yore, overlap 

 each other, as was pointed out by Arago in his ' M^moire sur 

 rfitat Thermom^trique du Globe terrestre' (' CEuvres,' v. 216, ed. 

 1858) in Palestine, when from this fact he, with much ingenuity, 

 argued that 3300 years have not appreciably altered the climate of 

 Palestine. For 



' la limite thermomdtrique en moins de la datte diff^re trfes peu de la limite ther- 

 momdtriqne en plus de la vigne ;' 



and, what makes the argument, especially to those who have 

 Kaempfer's picture of the luxuriant date-harvest before their eyes, 

 entirely and beautifully perfect, he further (p. 217, I.e.) tells us, 



' a Abusheer (Bushire) en Perse, dont la temperature moyenne ne surpasse certaine. 

 ment pas 23"", on ne pent, suivant Niebuhr, cultiver la vigne que dans les fosses ou 

 a I'abri de Taction directe des rayons du soleil.' 



A more simple, but also a more conclusive proof that the Syrian 

 climate has not materially changed within the historic period 

 cannot be imagined ^ 



I began this Lecture with details as to the distribution of pines 



1 It is strange to find that Arago could, when dealing with France, have swerved so 

 far from the line of evidence he employed as to Palestine, as to have told the Chamber 

 of Deputies (February 27, 1836), ' Vous serez peut-^re dtonnes d'entendre que dans 

 les environs de Paris, il y a quelques sifecles, il faisait beaucoup pluschaud qu'aujourd'hui.' 

 vol. xii. 'CEuvres, Melanges,' p. 434. But for the context one might have been 

 tempted to take the last of the words just quoted as applying to the month of Feb- 

 ruary only ; and in all gravity the title of chapitre xix. in the memoir already quoted, 

 vol. viii. ' (Euvres/ vol. v. ' Nat. Scient.' p. 239, ' Observations prouvant que I'ancien 

 climat se maintient dans une partie des Gaules,' might seem to justify such an inter- 

 pretation of words spoken under some provocation in debate. And the more so as a 

 few pages previously (p. 214) we find Arago recognising the essential deceptiveness 

 which must attach to ' une foule de documents historiques ' in the following words : 

 *0n remarquera que je devrai r^soudre le problfeme que je me suis pos^ sans avoir 

 recours k des chiffres certains, k des observations num^riques. L'invention des ther- 

 momfetres ne remonte gufere qu'a I'annee 1590; o^^^oit m6me ajouter qu'avant 1700 

 ces instruments n'^taient ni exactes ni comparables.' 



