APPENDIX II. 423 



use of the instrument ; on the contrary, it possesses the 

 singular advantage of detecting at once the inequality 

 where it exists, and of giving the mean dimensions of the 

 whole at the same time where the difference is not too 

 great. I have mixed together, for example, two small 

 specimens, which measured separately 21 and 31. The 

 mixture, though evidently irregular, gave the dimensions of 

 about 24, varying from 23 to 27, according to the part of 

 the lock which was to be examined, and this is surely a 

 much greater inequality than can ever exist in any 

 contiguous part of the same fleece. But, however this may 

 be, the fact is that the circumstance does not actually 

 destroy the validity of the indications of my micrometer, as 

 I shall further exemplify to you by an account of my ex- 

 aminations of some specimens of the finest wool, with which 

 I have been favoured by Mr. H. Sheppard, an ingenious 

 manufacturer at Frome, Somersetshire. You are, perhaps, 

 better acquainted than I am with the history of Mr. 

 Western's flock, which stands in so elevated a situation 

 between the Saxon and the Spanish productions. 



Specimens of Wool from Mr. Sheppard, as measured by the 

 Agricultural Thermometer. 



Grey beaver wool . . . No. 11J to 12 

 Angola ...... about 14 



Prime Vigonia 14J 



Foreign coney . . . . . .15 



American rabbits . . . . . ,15 



Yellow rabbits 15 



Scotch hares ...... 15 



Siberian hares 15, 16 



British coney . . . . . .16 



Finest seal ...... about 18 



Alpaca (a single long hair) .... 18^-20 



Goats . 19 



