80 PHILOSOPHICAL TRANSACTIONS. [ANNO 1 78 1 . 



they show. In their hurry they frequently miss their hold, and tumble down 

 the sides of the hill, but recover themselves as quickly as possible ; and, being 

 blind, bite every thing they run against, and thus make a crackling noise, while 

 some of them beat repeatedly with their forceps on the building, and make a 

 small vibrating noise, something shriller and quicker than the ticking of a watch: 

 Mr. S. could distinguish this noise at 3 or 4 feet distance, and it continued for a 

 minute at a time, with short intervals. While the attack proceeds they are in 

 the most violent bustle and agitation. If they get hold of any one, they will in 

 an instant let out blood enough to weigh against their whole body ; and if it 

 be the leg they wound, you will see the stain on the stocking extend an inch in 

 width. They make their hooked jaws meet at the first stroke, and never quit 

 their hold, but suffer themselves to be pulled away leg by leg, and piece after 

 piece, without the least attempt to escape. On the other hand, keep out of 

 their way, and give them no interruption, and they will in less than halfan hour 

 retire into the nest, as if they supposed the wonderful monster that damaged 

 their castle was gone beyond their reach. Before they are all got in you will see 

 the labourers in motion, and hastening in various directions towards the breach : 

 every one with a burthen of mortar in his mouth ready tempered. This they 

 stick upon the breach as fast as they come up, and do it with so much dispatch 

 and facility, that though there are thousands, and even millions of them, they 

 never stop or embarrass each other ; and you are most agreeably deceived when, 

 after an apparent scene of hurry and confusion, a regular wall arises, gradually 

 filling up the chasm. While they are thus employed, almost all the soldiers 

 are retired quite out of sight, except here and there one, who saunters about 

 among 6 hundred or a thousand of the labourers, but never touches the mortar 

 either to lift or carry it ; one, in particular, places himself close to the wall they 

 are building. This soldier will turn himself leisurely on all sides, and every now 

 and then, at intervals of a minute or two, lift up his head, and with his forceps 

 beat upon the building, and make the vibrating noise before-mentioned; on 

 which immediately a loud hiss, which appears to come from all the labourers,, 

 issues from within side the dome and all the subterraneous caverns and passages : 

 that it does come from the labourers is very evident, for you will see them all 

 hasten at every such signal, redouble their pace, and work as fast again. 



As the most interesting experiments become dull by repetition or continuance, 

 so the uniformity with which this business is carried on, though so very wonder- 

 ful, at last satiates the mind. A renewal of the attack however instantly 

 changes the scene, and gratifies our curiosity still more. At every stroke we 

 hear a loud hiss ; and on the first the labourers run into the many pipes and 

 galleries with which the building is perforated, which they do so quickly that 

 they seem to vanish, for in a few seconds all are gone, and the soldiers rush out 



