210 



NOTES AND MEMORANDA. 



rMonthly Jlicroscoplcal 

 L Journal, April 1, 1870. 



trivances which I hope will assist us in our pleasant microscopic studies. 

 The universal revolving stage consists of two plates of brass, in the 

 centre of which is a revolving disk, so constructed that different ap- 

 pliances may be placed in it. 



" The one before you has a live-box, which can be placed in the 

 centre, and by turning the milled edge will rotate, so that the object 



viewed may be seen at every 

 angle of light ; also a cork 

 disk upon which may be fixed 

 any object wished to be seen 

 in various positions ; and 

 an object-holder which does 

 equally well for transparent 

 or opaque-mounted objects. 

 This piece of apparatus is 

 the result of the desire to see 

 objects in different positions 

 and under every aspect. It 

 is made by Mr. J. Swift, 

 128, City Eoad. 



" The Tank Microscope 

 is constructed in a simple 

 and inexpensive way, which 

 may induce many to study 

 ' Life as it is ' in the aqua- 

 rium, without having to ex- 

 pend a large sum of money 

 for the purpose. It will be 

 observed that the ordinary 

 condenser is used as the stand 

 or pillar for the microscope, 

 which consists of a sliding arm, into which the body of the instrument 

 is placed ; and by having a revolving joint it can be moved in every 

 direction. On the pillar will be seen a small sliding, fitting into which 

 can be placed the stage forceps, leaf-holder, cork disk, &c., so that it 

 will be not only serviceable for tank work, but also for geological and 

 botanical purposes ; and by placing it in a vertical position, and using 

 a mounting table of block of wood, can be converted into a dissecting 

 microscope : this also is made by Mr. Swift." 



A Diatom Committee. — Captain Lang, the President of the Eeading 

 Microscopical Society, sends us a note, in which he makes the sugges- 

 tion that the Eoyal Microscopical Society should appoint a Committee 

 of Eeference for those who are engaged in diatom inquiries. " In last 

 month's number of ' Science Gossip,' in an entire article by L. G. Miles 

 "On Guano Diatoms," there is a proposal worth consideration. After 

 giving examples of abnormal forms, and remarking on the tendency 

 towards extensive multiplication of supposed new species on insuffi- 

 cient grounds, this writer suggests that as the Eoyal Microscopical 

 Society, as a national institution, is now looked up to as a guide to 

 British microscopists generally, it would be well that a Committee 



Mr. Blankley's Tank Microscope. 



