82 



From these experiments uncorrected for ellipse, we have, — 



Exp. 6. 8. On N.E. and S.W. line ii±i^=13°-0 in one hour. 



2 



7. 9. On N.W. and S.E. linei^^^55±il:lP = io°-88. 



2 



I have since made a great variety of experiments with this apparatus, 

 which, notwithstanding the theoretical and practical disadvantage of 

 working with so short a pendulum, I hope to render accurately- 

 effective, so that the angular deviation of the pendulum-plane may 

 become an ordinary and easy experiment. It should, however, be 

 tried In a glass case, and probably in vacuo. 



4. " Note on instantaneous Photographic Images." By H. F. 

 Talbot, Esq., F.R.S. &c. 



" Having recently met with a photographic process of great sensi- 

 bility, I was desirous of trying whether it were possible to obtain a 

 truly instantaneous representation of an object in motion. The ex- 

 periment was conducted in tlie following manner. A printed paper 

 was fixed upon a circular disc, which was then made to revolve on 

 its axis as rapidly as possible. When it had attained its greatest 

 velocity, an electric battery, kindly placed at my disposal by Mr. 

 Faraday, was discharged in front of the disc, lighting it up with a 

 momentary flash. A camera containing a very sensitive plate of 

 glass had been placed in a suitable position, and on opening this 

 after the discharge, an image was found of a portion of the words 

 printed on the paper. They were perfectly well-defined and wholly 

 unaffected by the motion of the disc." 



"As I am not aware that this experiment has ever succeeded, or 

 indeed been tried, previously, I have thought it incumbent on me to 

 lay an early account of it before the Royal Society." 



5. " On the Impregnation of the Ovum, in the Amphibia 

 (Second Series), and on the Nature of the Impregnating Influence." 

 By George Newport, Esq., RR.S.,F.L.S.&c. Received June 19, 1851. 



The author commences his paper by stating that, having given 

 direct proof, in his former paper, that the spermatozoon is the im- 

 pregnating agent, and also that the liquor seminis does not effect 

 impregnation, he now proposes to detail some new experiments 

 which bear on the views he then advanced; and especially with 

 respect to the nature of tJie impregnating influence. 



He first details some additional experiments with solution of car- 

 mine, with the object to show, that the result of one experiment men- 

 tioned in his former paper, in which he detected a small, granule of 

 carmine within the vitellary membrane, was attributable to the cause 

 he then assigned — accidental injury to the egg; and he states that 

 the results of his present investigations confirm him in the view then 

 held, — that no natural perforation or fissure exists in the envelopes 

 of the egg, either of the Frog or of the Newt, before, or at the 



