490 THEPHILOSOPHY 



idea of their numbers, the reader •will not be difpleafed to fee Dr 

 Harvey's fliort account of the Bafs. ' There is a fmall ifland in the 

 Frith of Forth, called the Bafs Tjland, which does not exceed a 

 mile in circumference. The furface of this ifland, during the 

 months of May and June, is fo entirely covered with nefts, eggs, 

 and young birds, that it is fcarcely poflible to walk without tread- 

 ing on them. The flocks of bird§ on the wing are fo prodigious, 

 that they darken the air like clouds, and their noife is fo great, 

 that a man cannot without difficulty hear his neighbour's voice. 

 If, from the top of the precipice, you look down upon the fea, 

 you will fee it on every fide covered with infinite numbers of 

 birds of different kinds, fwimming about and hunting for their 

 prey. When failing round the ifland, if you furvey the hanging 

 cliffs, you will perceive, in every cragg, or fiflTure of the rocks, in- 

 numerable birds of various kinds, more than the ftars of heaven 

 in a ferene night. If you view the difliant flocks, either flying to 

 or from the ifland, you will imagine them to be a vaft fwarm of 

 bees *.' The rocks of St Kilda feem to be equally frequented by 

 folan geefe ; for Martin, in his defcription of the Hebrides, informs 

 us that the inhabitants of this fmall ifland confume annually no lefs 

 than 22,600 young birds of this fpecies, befide an amazing number 

 of their eggs. The folan geefe and their eggs confl:itute the chief 

 food of thefe iflanders. They preferve both the fowls and the eggs 

 in fmall pyramidal fl;one buildings, which, to protect the food from 

 moifl:ure, they cover with the aflies of turf. The folan geefe are 

 birds of pafl!age. Their firft appearance is in March, and they con- 

 tinue till Auguft or September. But, in general, the times of their 

 breeding and departure feem to coincide with the arrival of the her- 

 ring, and the migration of that fifh from our coafts. It is more than 

 probable that thefe birds attend the herrings and pilchards during their 



whole 



* Harvey de Generat. Animal. Exercit. 11. 



