Septembeb 1, 1922] 



SCIENCE 



253 



tion of the retinal image ahows that it ia inverted 

 and tranaposed. ' ' 



The experiments suggested here by Hartridge 

 are well enough known, but his summary calls 

 definitely to mind the fact that it is by the 

 use of one or the other of these experiments 

 that demonstration of the actual position and 

 of the inversion of the image in the eye of a 

 mammal must usually be presented to classes 

 of students in physiology, whenever direct evi- 

 dence is given at all. Difficulties often arise 

 in carrying out either experiment. The eye 

 of an albino as large as a rabbit is very often 

 not easily obtainable. Since the eye of sueJi 

 an "ordinary animal" as the pdg may almost 

 always be had from the butcher or the meat 

 inarket so soon after the animal has been killed 

 that the dioptrical parts are still transparent, 

 the ordinary eye would seem to be the obvious 

 one to use for such demonstrations. As a 

 matter of fact, however, the preparation of the 

 demonstration with a pigment-bearing eye is 

 rendered always somewhat uncertain, on ac- 

 count of the difficulty of removing the choroid 

 and the retinal pigment without puncturing 

 the retina and thus destroying its value as a 

 screen on which to see the image. I have found 

 it easy to complete the demonstration of the 

 invei-ted image in such cases by carefully 

 cutting out a little' window of about 5 mm. 

 diameter in the retina and then pressing over 

 this window until it sticks fast against the 

 vitreous humor a small piece of thin paraffine 

 paper. Standing in the place of the retina, 

 this paper forms a very good screen upon 

 which to receive the image. 



An incandescent electric light forms an ex- 

 cellent object for use in the demonstration, 

 which is always an interesting one to students 

 and certainly quite conclusive, as Hartridge 

 says. 



Geo. D. Shafer 



LeLAND STANrORD, JR., UNrVERSITT. 



QUOTATIONS 

 SPIRIT PHOTOGRAPHS 



There is a society or club known as the 

 Magic Circle which consists of professional 

 conjurers, but admits a few approved ama- 

 teurs, to the kindness of one of whom, a dis- 



tinguished member of the medical profession, 

 we are indebted for a copy of a report, dated 

 May 31, issued by the Occult Committee of the 

 Circle. This comniittee, which consists of ex- 

 pert conjurers, has been appointed to investi- 

 gate what are called "spiritualistic phenom- 

 ena," and at the suggestion of Sir Arthur 

 Conan Doyle appears to have turned its atten- 

 tion first to spirit photographs. The report 

 deals with the inquiries made by the committee 

 into the claims of two people — a. man and a 

 woman — who it was alleged were producing 

 spirit photographs of a remarkable nature in 

 unopened packets of photographic plates. 

 Neither of the mediums came out of the ordeal 

 unscathed. When a fraud-proof packet was 

 sent to the male operator he obtained no re- 

 sults. He stated that the packet had twice 

 been "held," but that the "usual sensation" 

 had not been felt. As soon, however, as a 

 packet that could be tampered with was sub- 

 mitted, a "psychic extra," as it appears to be 

 called, was obtained on one of the plates. Un- 

 fortunately for the performer the conjurers 

 had tampered with the packet first. In addi- 

 tion to other tests, a straight line of red var- 

 nish (invisible in the red light of the dark 

 room) had been painted across the top left 

 side of the edge of the Stack of six plates. On 

 the return of the packet by the medium three 

 of the red marks were found at the bottom, 

 showing that these plates had been reversed. 

 When the operator was asked for an assurance 

 that the packet had really been returned un- 

 opened, he replied in the affirmative. He said 

 that it was quite usual to get adverse remarks 

 from persons who did not understand, and that 

 such remarks were not worthy of notice. Shall 

 we admire the power of spirits, or deplore the 

 frailty of human nature? The lady medium 

 was vouched for by Mr. and Mrs. Hewat 

 McKenzie, who conduct an institution known 

 as the British College of Psychic Science. 

 Three sittings were held with this medium. 

 First, two members of the committee secured a 

 private sitting. It was required that the 

 plates, enclosed in a sealed packet, should be 

 sent for "magnetization" some days in ad- 

 vance, and at the sitting these plates were ex- 

 posed, and on develoiament "extras" were on 



