 To look at anything means to place the eye in such a position that the image of the object falls on the small region of perfectly clear vision. This we may call direct vision, applying the term indirect to that exercised with the lateral parts of the...  The British Journal of Photography - Page 2231878Full view - About this book
 | Hermann Ludwig F. von Helmholtz - 1873 - 424 pages
...can bring her image to a focus upon the central pit of our retina. Then only are we able to see her. To look at anything means to place the eye in such...retina — indeed with all except the yellow spot. The defects which result from the inexactness of vision and the smaller number of cones in the greater... | |
 | Hermann von Helmholtz - Physics - 1873 - 432 pages
...can bring her image to a focus upon the central pit of our retina. Then only are we able to see her. To look at anything means to place the eye in such...retina — indeed with all except the yellow, spot. The defects which result from the inexactness of vision and the smaller number of cones in the greater... | |
 | William Jackson - Natural theology - 1874 - 432 pages
...bring her image to a focus upon the central pit of our retina. Then only are we able to see her. " To look at anything means to place the eye in such...— indeed with all except the yellow spot. " The defects which result from the inexactness of vision and the smaller number of cones in the greater... | |
 | William Jackson - 1874 - 436 pages
...image to a focus upon the central pit of our retina. Then only are we able to see her. " To I 'in I; at anything means to place the eye in such a position...— indeed with all except the yellow spot. " The defects which result from the inexactness of vision and the smaller number of cones in the greater... | |
 | William Jackson - Natural theology - 1875 - 452 pages
...bring her image to a focus upon the central pit of our retina. Then only are we able to see her. " To look at anything means to place the eye in such...indirect to that exercised with the lateral parts of the retina—indeed with all except the yellow spot. " The defects which result from the inexactness of... | |
 | Christopher Smith Fenner - 1875 - 360 pages
...eye is like a picture, minutely finished in the centre, but only roughly sketched in at the borders. To look at anything, means to place the eye in such...the small region of perfectly clear vision. This we call direct vision, applying the term indirect to that exercised with the lateral parts of the retina... | |
 | Edwin Samuel Gaillard - Medicine - 1878 - 604 pages
...longing for release usually experienced, it seemed to me that I could have sat on without effort. As Helmholtz clearly puts it, " to look at anything means to place the eye in such a position that the imnge of the object falls on the small region of perfectly clear vision. This we may call direct vision,... | |
 | Elroy McKendree Avery - Physics - 1878 - 480 pages
...yardFIG. 279. stick. Place the tip of a candle flame opposite one of the divisions of the stick, and place the eye in such a position that the image of the top of the flame will be seen in the direction of the foot of the plumb-line. Mark the point where... | |
 | Hermann von Helmholtz - Science - 1883 - 432 pages
...can bring her image to a focus upon the central pit of our retina. Then only are we able to see her. To look at anything means to place the eye in such...indirect to that exercised with the lateral parts of the retina—indeed with all except the yellow spot. The defects which result from the inexactness of vision... | |
 | Peter Henry Emerson - Art and photography - 1890 - 358 pages
...to see a lark in the sky, Helmholtz says it must be focussed on the central spot. Finally he says, " To look at anything means to place the eye in such a Direct and position that the image of the object falls on the small indirect region of perfectly clear... | |
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