6 TOPOGRAPHY 



of equestrians, as riding on this fine turf, except 

 during the race weeks, is considered tantamount to 

 trespassing within a convent's wall, and it is almost a 

 pity, that even the cows which furnish the best milk 

 for the garrison, should be allowed to graze on this 

 prolific soil, which evidently has been only recently 

 formed (I believe by order of the late General Don) 

 from the debris of the garrison and elsewhere. Hence 

 many plants are found in this space which are not 

 usually seen in similar situations in this part of 

 Andalusia, and some of them are not even found 

 for miles beyond it, such as the Muscari comosum, 

 Ranunculus bullatus, Hyoscyamus albus, Tribulus 

 terrestris, &c. 



This isthmus is, in most parts of its extent, about 

 ten feet above the level of the sea. Its breadth 

 near the rock is nine hundred and fifty yards ; it 

 gradually increases, and midway its breadth is about 

 twelve hundred yards ; and near the Spanish lines 

 it measures across about seventeen hundred and fifty 

 yards ; it still goes on increasing till it is lost in the 

 level ground at the foot of the mountain called 

 " the Queen of Spain's chair." Its circumference 

 is nearly eight miles. This neck of land, as far as 

 could be ascertained, is entirely composed of sea-sand, 

 in which are found large quantities of sea-shells as 

 has already been observed, and from the nature of 

 the rocks in the neighbourhood, it must naturally 

 be concluded that this bed of sand rests on a lime- 

 stone formation, but hitherto this has not been -de- 

 monstrated, as the sand has not been removed to 



