l888.] NEW YORK MICROSCOPTGAL SOCIETY. 159 



and depression of these spines, causing a change in form of the 

 surface of the scales. 



A " WEBB " WRITING OF THE LORD's PRAYER. 



Mr. Charles S. Shultz stated that the slide exhibited by him, 

 the property of Mr, Stephen Helm, was written by Mr. Webb, 

 of England, and that, with the use of letters of the same size, 

 twenty Bibles could be written in the space of a square inch. 



In the London Monthly Microscopical Journal, October, 1876, 

 p. 172, it is recorded, that Mr. Frank Crisp of London had then 

 in his possession a diamond engraving of the Lord's Prayer, 

 written at the rate of fifty-nine Bibles to the square inch. 



CONTINUOUS CENTERING OF A COVER-GLASS, 



The Rev. J. L. Zabriskie : " I find that a very satisfactory 

 method for the continuous centering of a cover-glass, for sub- 

 sequent operations with the self-centering turn-table, with either 

 a glycerine or a balsam mount, when no cell is employed, is to 

 run a very delicate ring of india-ink with a fine pen upon the 

 upper, or clean side of the glass slip, while the slip is revolving 

 upon the turn-table, and one thirty-second of an inch larger 

 than the cover about to be used, as the first step in the operation 

 of mounting, 



" I have heard of such rings being employed on the under 

 side of the slip. But very few of the latter are such accurate 

 parallelograms that a ring on the under side will be central for 

 the upper side, because, when the slip is turned over, it is liable 

 to be held on the turn-table by the pair of diagonal corners, 

 which were not employed in the first instance. And moreover 

 when the ring is run on the under side, the thickness of even a 

 thin slip renders difficult the subsequent centering of a cover by 

 sight, 



"If the ring of ink is run on the clean side of the slip it is 

 accurately centered for each subsequent operation ; the cover 

 can be centered within it accurately without returning to the 

 turn-table; and if the application of a spring-clip causes the 

 cover to slide, the latter can still be immediately readjusted by 

 sight. 



" The india-ink dries at once, and does not, as might be sup- 

 posed, cause any practical difficulty by running in under the 



