20 TOPOGRAPHY 



succinctly of other matters connected with its physical 

 history ; and first in importance to the inhabitants 

 of a large garrison like Gibraltar, are the sources of 

 the water which they consume. From the nature of 

 the soil, and the immensity of the sand-deposits 

 within the garrison, we can easily imagine the exist- 

 ence of springs ; still the number of springs is not 

 great, and the few wells which exist, are very 

 deep, and appear to be supplied from percolation of 

 rain-water, within the narrow limits of the rock itself; 

 which circumstance was taken advantage of by the 

 Moors during their possession of the rock, and they 

 accordingly constructed an aqueduct which has been 

 since destroyed. The present one, planned by a 

 Spanish Jesuit, conveys the water collected by perco- 

 lation through the red sands in a reservoir or well near 

 Victoria Battery, into the centre of the town, and 

 terminates at the Commercial-square. The water 

 obtained from the wells is hard, being slightly im- 

 pregnated with lime, but it is considered wholesome. 

 More than one half the water used in Gibraltar is 

 collected in tanks or cisterns from the rains which 

 fall during the year. Nearly all of the modern 

 houses possess this requisite appendage. There are 

 also public tanks of immense capacity; many of them 

 have been recently built for the use of the troops. 

 The largest of these tanks are those which supply 

 water to the Navy; they are said to be capable of 

 holding nearly one million four hundred thousand 

 gallons of water ; and all the other tanks in the gar- 

 rison, both public and private, upwards of two million 



