96 



branches, and no portion of the book showed the need o£ such 

 assistance more than the chapter on mounting, so that a young 

 microscopist would not be able to obtain from that chapter help 

 which would enable him to mount an insect in a satisfactory 

 way. There were few books, even of less technical character, 

 of which it could be said that they were absolutely perfect, 

 whilst with regard to this it would be freely admitted that 

 those portions to which Dr. Dallinger had given personal 

 attention were very admirably done. 



Mr. H. Morland read a paper " On a Method of Mounting 

 Diatoms," specimens of the metal discs mentioned being ex- 

 hibited in illustration. 



Mr. Hailes said he had used something very like this plan 

 for some years in mounting Foraminif era, only instead of using 

 metal he had found discs of paper or card to be best ; they were 

 easily punched out with a pair of shoemaker's pincers, and the 

 materials could be obtained of any thickness. Balsam ran in 

 quite freely, so that practically the card or paper disc was 

 mounted in balsam with the object. 



Mr. Morland said that his object in using metal was to 

 know exactly the thickness between the cover and the slide. It 

 was not merely for the sake of protecting the diatoms. 



The Chairman said no doubt all who were in the habit of 

 mounting objects were accustomed to use something to prevent 

 the cover glasses from pressing upon delicate objects. He had 

 himself sometimes used small glass beads for the purpose, but 

 this was a very different matter from that aimed at by Mr. Mor- 

 land, who wanted to get a substance of a certain definite thick- 

 ness, and this not only kept oU the pressure, but gave him an 

 easy means of regulating the distance between the cover and the 

 slip. He thought the suggestion would be of value to those 

 who wanted to mount very minute flat" objects for examination 

 under very high powers. He had, however, been under the 

 impression that gum or any other adhesive mixture was not 

 advantageous and not necessary in mounting objects of this 

 kind. 



Mr. Morland said that some forms could be mounted very 

 well without. 



The thanks of the meeting were unanimously voted to Mr. 

 Morland for his communication. 



