NATURAL HISTORY. 127 



snapping together and making quite a noise. 

 Some of them too (perhaps they are the officers) 

 are constantly beating with their awls upon the 

 outside wall, and make a sound something 

 quicker and sharper than the tickingof a watch. 

 You may hear it at a distance of three or 

 four feet.. When these biters lay hold, nothing 

 will make them let go ; you must tear them 

 away by pieces. After you stop striking the 

 wall, in about half an hour they seem to get 

 over their rage and go back into the city, and 

 then out come the labourers. While the noise 

 continues you will not see one of them ; they 

 all fled at the first appearance of danger. But 

 now they come, each one with a bundle of 

 mortar in his mouth, ready made ; and they 

 stick it on the hole so fast, and with such 

 order, that though thousands and thousands 

 are at work they never interrupt each other. 

 And while the labourers are busy, if you look 

 you may commonly see a soldier or two walk- 

 ing about ; but they never touch the mortar, 

 nor help in any way to mend the hole. One 

 of these soldiers always stands near the spot 

 where the labourers are at work, and every 

 now and then turns slowly around, and fre- 

 quently lifts up his head, and with his awls 



