FELTINa 43 



Btruction at last of a superior achromatic microscope by Mr. 

 Powell, of London, enabled him to realize his ardent wishes ; 

 and his own description of the scene, and the conclusions 

 to which he arrived, are of too much interest to admit of 

 any abbreviation. 



« On the evening of the 7th of Feb. 1835, Mr. Thomas 

 Flint, woollen manufacturer, resident at Leeds ; Mr. Sy- 

 monds, clothing agent, of London, Mr. F. Millington, sur- 

 geon, of London, Mr. Edward Brady, veterinary surgeon, 

 Mr. Powell, the maker of the microscope, and the author 

 himself, were assembled in his parlor. The instrument was, 

 in Mr. Powell's opinion, the best he had constructed. A 

 fibre was taken from a Merino fleece of three years' growth ; 

 the animal was bred by, and belonged to Lord Western. It 

 was takeir without selection, and placed on the frame to be 

 examined as a transparent object. A power of 300 (linear) 

 was used, and the lamp was of the common flat-wicked kind. 

 The focus was readily found ; there was no trouble in the 

 adjustnient of the microscope; and after Mr. Powell, Mr. 

 Plint had the first perfect occular demonstration of the ir- 

 regularities in the surface of the wool, the palpable proof of 

 the cause of the most valuable of its properties — its disposi- 

 tion to felt. 



"The fibre thus looked at, assumed a flattened riband- 

 like form. It was of a pearly grey color, darker towards 

 the centre, and with faint lines across it. The edges were 

 evidently hooked, of more properly serrated — ^they resembled 

 the teeth of a fine saw. These were somewhat irregular in 

 difiereiit parts of the field of view, both as to size and num- 

 ber. , The area of the field was now ascertained ; it was 

 one-fortieth of an inch in diameter. By means of the mi- 

 crometer we divided this into four, and we then counted the 

 number of serrations in each division. Three of us counted 

 all four divisions, for there was a difference in some of them. 

 The numjier was set down privately, and it was found that 

 we had all "estimated it at fifteen in each division. Having 

 multiplied this by four, to obtain- the whole field, and that by 

 forty, the proportionate part of an inch of which -the field 

 consisted, we obtained a result which could not be disputed, 

 that there were 2,400 serrations in the space of an inch, and 

 all of which projected in the same direction, viz. from the 

 root to the point. Then, before we quitted the examination 

 of the fibre as a transparent object, we endeavored to ascM- 



