I 



THE MICROSCOPE. 207 



A NEW BACTERIUM. 



BY J. M. ADAMS. 



T appears that a new bacterium comes into existence, a little dif- 

 ferent from the ordinary seDtic bacteria, at the close of decom- 

 position, or, when organic infusions are being resolved into clear 

 and odorless liquids with gray, inert powdery sediments which gen- 

 erally takes a year or two before this work is completed. This new 

 form resembles the B. termo, but only about one-half its size, single 

 celled, oblong and probably biflagellate. It is evidently not an 

 impoverished form of the termo, for it is very active, generic-of its 

 own kind and actually consumes the termo which has up to this 

 time done the principal work of decomposition. 



Whether this bacterium can live at any other time is a question. 

 It requires a clear, strong daylight and a short tube to be seen at all 

 and for its peculiar lateness may have been unobserved. 



GLEANINGS FROM THE JOURNAL OF THE ROYAL 

 MICROSCOPICAL SOCIETY FOR OCTOBER. 



BY C. H. STOWELL. 



ASSYRIAN LENS.— Sir A. Henry Layard, in his " Nineveh and 

 Babylon," describes a lens which he found in the course of his 

 excavations and which is now in the British museum. It is a plano- 

 convex rock-crystal lens. It was found buried beneath a heap of 

 fragments of beautiful blue opaque glass, apparently the enamel of 

 some object in ivory or wood, which had perished. 



The length of the lens is i T ^- in., and its breadth 1/5- in. It is 

 about % in. thick. It is poorly polished and scratched. It gives a 

 tolerably distinct focus at 4^ in. from the plane side. In all prob- 

 ability this lens was used by the Assyrians for magnifying purposes. 



The Compound Microscope. — Professor Heschl, of Vienna, 

 found nine compound microscopes in Austria. One was made be- 

 tween the years 1760 — 90. It stands 32 cm. high and is provided 

 with seven objectives and two Lieberkuhns. One instrument had a 

 stage, 12 cm. by 9 cm., consisting of a lower plate carrying a wheel 

 of diaphragms, and an upper plate sliding between two pieces sup- 

 ported on four short uprights. The eye-piece was Huyghenian and 

 the mirror made of metal. 



