36 
The President's Address. 
An achromatic condenser, made by Mr. Ross, with a large- 
angled -Vths, possesses in a high degree the properties alluded 
to in these remarks ; though Messrs. Powell and Lealand’s 
large-angled condenser must be preferred when difficult 
surface markings are to be displayed. 
Professor Smith, of Kenyon College, U.S., whose name is 
well known to English microscopists, is now in this country ; 
and he has brought with him a series of remarkably beautiful 
drawings of diatoms in a live state, illustrating new views of 
their structure and mode of propagation. These it is hoped 
he will be able to show at the next meeting of this Society, 
and to add explanations of the curious and important results 
at which he has arrived. English observers have, in too 
many cases, confined their attention to dry and dead valves 
of the diatoms ; but it may he expected that Professor Smith’s 
researches will excite renewed attention to the living forms. 
Professor Smith has likewise brought with him a binocular 
eye-piece adapted for use with a single-tube microscope, 
which is considered by those who have tried it in this country 
to give much better results than had been previously obtained 
by a similar construction. He has also devised a mechanical 
finger, which is described in c Silliman’s Journal,’ No. 123. In 
this instrument a movable arm readily attached to the 
microscope carries a bristle, which can be made to touch and 
lift up any minute object seen under a moderate power on a 
glass slide. As soon as the mechanical finger has caught the 
object, it is raised, and a clean slide placed on the stage. The 
bristle carrying its minute .burden is then brought into focus, 
and made to deposit it on the centre of the slide. With this 
little instrument very minute objects can be sorted and 
arranged with great ease. 
Last year, illuminators for opaque objects under high 
powers were brought before the Society by Messrs. Powell 
and Lealand, and Richard Beck. They were both founded 
upon plans originally tried by Professor Smith, who did not 
like their performance, and he is now able to show us the 
form of metallic reflector which he recommends, and which 
affords better results. Mr. Smith, of Bow, has likewise de- 
vised an arrangement slightly differing from that of Professor 
Smith, which is well spoken of. 
One pleasing feature of our times is the formation of 
scientific societies in connection with great mercantile 
houses. Foremost amongst these, in point of date, excellent 
management, and important success, is the Old ’Change 
Microscopical Society, formed in the establishment of Messrs. 
Leaf. Your President and Council, appreciating the service 
