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Jim OU NT KAN&E. [From The Medical News, October 9, 1886.] 
A NEW SERIES OF METRIC TEST-LETTERS 
AND WORDS FOR DETERMINING THE 
AMOUNT AND RANGE OF ACCOM- 
MODATION.1 
CHARLES A. OLIVER, M D , 
ONE OF THE OPHTHALMIC AND AURAL SURGEONS TO ST. MARY'S 
HOSPITAL, PHILADELPHIA, ETC. 
This set of reading-types has been made upon the 
same basis that governed the test-types presented at 
last year's meeting of the Society. By reason of this 
conformity an examination of acuteness of vision and 
accommodative action by means of these two series 
serves to place the results upon a uniform and proper 
foundation. The following advantages over other 
reading-types may be claimed : 
First, the Letters. The Snellen block letter has been 
preserved. 
Second, the Character and the Arrangement of the 
Words. The letters C D E T O L F are made into 
words of one or two syllables, and placed in columns. 
They are so arranged that a word composed mainly of 
vertical and horizontal strokes is followed by a word 
made of a majority of curved lines, no matter in what 
vertical or horizontal direction the columns may be 
read. 
Third, the Sequence. The smallest type is placed 
first, each increasing type following in succession, 
until one equivalent to two dioptrys is reached, which 
finishes the card, leaving but a half dioptric separation 
between this card and the large one. 
Fourth, the Interspace. Each word and letter is 
surrounded by a space equal to or greater than its own 
area, thus preventing any letter or word from being 
confounded with its neighbors. 
Fifth, the Gradation. The following sizes are em- 
ployed : 0.25 D., 0.50 D., 0.75 D., 1 D., 1.50 D., and 2 D. 
Sixth, the Construction. The letters are phototypes. 
The card is made of heavy neutral gray cardboard, 
with rounded corners. The letters are printed upon a 
sunken surface, thus keeping them free from dirt by 
contact through handling, or by the card being placed 
upon dirty surfaces. 
James W. Queen & Co., of 924 Chestnut Street, Phila- 
delphia, have kindly superintended the construction of 
the cards, and to them the author here desires to ex- 
press his thanks for careful and satisfactory work. 
1 Abstract of a paper read before the American Ophthalmo- 
logical Society, July 22, 1886.