PROCEEDINGS OF THE SOCIETY. 
547 
ordinary chair, and had found no inconvenience. He remembered the 
photograph in Zeiss’s catalogue, and agreed that the figure viewing the 
Microscope looked very uncomfortable. As to the precisely best method 
of focusing from a distance, he thought Mr. Nelson was wrong in 
supposing there was only one really good method. He had used a 
Hooke’s joint for focusing in Zeiss’s photographic room at Jena on 
several occasions, the illumination being an arc lamp, and projecting the 
images on a distant screen, and he found it quite convenient. He had 
tried a number of pulley arrangements, most of which had seemed to him 
fairly efficient. Excellent work could be done with very various means. 
No one had exhibited better work than Mr. Thomas Comber, who used 
a Zeiss Microscope, and who sat down while adjusting the instrument, 
as would be seen in the woodcuts that would be published in the August 
Journal. It should be remembered that Mr. Pringle had had the 
advantage of knowing Mr. Nelson’s apparatus and methods, so that any 
variations he had devised were considered by him as improvements. He 
was sorry Mr. Pringle was not present to meet Mr. Nelson’s criticism. 
The Chairman said Mr. Nelson had criticized the new apparatus in 
his characteristic manner. He thought the subject had taken up as much 
time as could well be allowed, considering the other matters on the 
Agenda. He would, therefore, not ask any one to continue the discussion, 
but would at once call upon the meeting for a vote of thanks to 
Mr. Andrew Pringle for sending the apparatus for exhibition, and to 
Mr. Mayall for the description he had given of it. 
Mr. E. M. Nelson exhibited upon the screen two photographs of 
bordered pits of pine wood, taken from sections prepared and mounted 
by Mr. Suffolk. He thought these pictures showed clearly that the 
pits were of the nature of clack-valves, and probably served the purpose 
of checking the downward pressure of fluid in the vascular system, which, 
in the case of a tree 150 feet high, would amount to about 75 lb. to the 
square inch. He also showed some new photographs of diatoms 
X 1350. 
Mr. Mayall said a paper had been received from Mr. Charles E, West, 
of Brooklyn, on “Early Binocular Instruments.” After giving a summary 
of the contents, he pointed out that the paper was rather remarkable for 
the omission from it of any allusions to binocular instruments of earlier 
date than Rheita's ‘ Oculus Enoch et iElim, sive Radius Siderio Mysticus,’ 
published in 1645. The modern text-books of the history of physics, 
&c. — such as Grant’s £ History of Physical Astronomy/ or Poggendorff’s 
* Geschichte der Physik,’ or Harting’s 4 Das Mikroskop * — all referred 
to the official documents discovered at La Haye in the early part of the 
century by Van Swinden, whence it was proved that upon Lippershey’s 
pressing for a money recognition from the States General in 1608, for 
his newly-constructed telescope, the payment was deferred until he could 
perfect the instrument by making it available as a binocular, which he 
did before the end of the same year. Then, as to the invention of 
binocular Microscopes, their American friend was content to quote from 
Zahn’s ‘ Oculus Artificialis Teledioptricus, sive Telescopium,’ published 
in 1685, apparently oblivious that Zahn was not an original authority 
on the matter, but that he had roughly summarized from Cherubin 
