242 



Mr. E. A. Schafer on the 



[Apr. 3, 



all these, a single curve and table for reducing all the observations to the 

 same zenith-distance was obtained, which proved to be nearly, but not 

 quite, the same as that found by Professor Seidel for the light of the 

 stars. By employing the table thus deduced, and also reducing the heat- 

 determinations obtained on the various nights for change of distance of 

 the sun, a more accurate phase-curve was deduced, indicating a more 

 rapid increase of the radiant heat on approaching full moon than was 

 given by the formula previously employed, but still not so much as Pro- 

 fessor Zollner's gives for the moon's light. 



By employing Laplace's formula for the extinction of light in our 

 atmosphere, the heat-effect in terms of the scale-readings was deduced, 

 and an approximation to the height of the atmosphere attempted. 



Prom a series of simultaneous measurements of the moon's heat and 

 light at intervals during the partial eclipse of November 14, 1872, when 

 clouds did not interfere, it was found that the heat and light diminish 

 nearly if not quite proportionally, the minimum for both occurring at or 

 very near the middle of the eclipse, when they were reduced to about half 

 what they were before and after contact with the penumbra. 



April 3, 1873. 



WILLIAM SHARPEY, M.D., Vice-President, in the Chair. 



The following communications were read : — 



I. "On the Structure of Striped Muscular Fibre/'' By Edward 

 Albert Schafer. Communicated by Dr. Sharpey, V.P.R.S. 

 Received March 13, 1873. 



(Abstract.) 



After premising that, owing to the rapidity with which changes set in 

 after death, the subject in question can only properly be worked out 

 whilst the muscular fibres are still living, the author proceeds to give 

 the result of his investigations of the tissue in this condition. The 

 animal employed was the common large water-beetle, the muscles of the 

 legs being taken. These were examined entirely without addition, being 

 either teazed out upon a glass slide in the ordinary way and covered 

 with thin glass, or else prepared upon the latter, which was then inverted 

 over a ring of putty after the method introduced by Strieker. 



The author describes a muscular fibre as consisting of a ground- 

 substance appearing at first sight to be formed of two distinct substances 

 (the one dim, the other bright in aspect, which are arranged in alternating 

 disks disposed in successive series, with their planes at right angles to 



