go O F S T O N E S. 



5. A pebble with crufts of a deep amber-colour, and a bright 

 white ; an inch and a half long, and an inch and a quarter 

 broad. From the fti-ore of the Tweed. 



There are many others on the fame mores, where the curious 

 lithologift might meet with much entertainment after greatfloods. 

 They have all exterior coats in their perfect ftate, like thofe of 

 flints, which are very fcarce with us. 



There is a fine collection of TW^-pebbles in the poiTeilion of 

 nay worthy friend, Henry Cotting'wood, of CombiH* Efq; many fine 

 Carnelians among them. There is alfo a neat collection of Bo-w- 

 m>-pebbles in the poffeffion of Mrs. Selty r .of Pa/ton. 



Of Agates we have the following kinds and varieties. 



1. An agate-lithoftrotion, compofed of cryftaline columns, the 

 ends forming a wavy reticular work, a light yellow in the center; 

 encircled with black ; the malhes white ; large, and ponderous. 

 From the fhore of North Tyne, by the iflet near Chipchace-rmll. 



2. An zgatz-lithoftrotion, compofed of large aftroite finds, of a 

 button-lik lhape, of a corneous, flinty texture, yellow, edged 

 with white ; having much the appearance after politure of the 

 great fora//ozV/-lithoftrotion. From the fhore of the river Tyne, 

 below Hexhant. 



The celebrated Dr. /&7/judicioufly obferves, that foffil corals 

 are fometimes fo fated with cryflalline matter, that they are con- 

 creted into mere agates (k). 



3. An agate of a ftrong and deep red, variegated with a florid 

 red, a pale blue, green, and yellow of different degrees, in beau- 



(k) Hill. Hift. Foff. p. 642. 



tiful 



