52 COERESPONDENCE. 



the vestiges of stipes), Gomphonema, &c. Mr. Wood's discovery ! ! 

 will therefore not do much in altering the opinions of naturalists 

 as to the vegetable nature of the Diatoraaceae, and it is probable 

 a few years' study of these forms will satisfy him that they are as 

 much vegetable as the Desmids or any other of the simpler forms of 

 algfe. 



I remain, Sir, yours, &c., 



F. KiTTON. 



" Microscopical Science." 



To the Editor of the ' Monthly Microscopical Journal.^ 



SiB, — F.E.M.S. says, in his remarks on Mr. Branwell's proposed 

 prize for the best objective, " I remember some years ago a large 

 sum of money was subscribed to the ' Quekett Memorial Medal Fund/ 

 to be given at the discretion of the Council to such member of the 

 Society who, in the opinion of the Council, has best promoted the in- 

 terest (ii Microscopical Science" Like Mr. Clennam, " I want to know " 

 what is " microscopical science," and I fear until this question is 

 satisfactorily answered the gold medal will not be struck. Although 

 ashamed of my crass ignorance, I do not hesitate to attach my name 

 to this inquiry. 



Your obedient servant, 



F. KiTTON. 



A New Form of Freezing Microtome. 



To the Editor of the ' Monthly Microscopical Journal.' 



Pendlebury, Manchester. 



Sir, — In all the freezing microtomes hitherto described, the 

 requisite degree of cold is produced by the use of a freezing mixture 

 of ice and salt, the preparation of which is so troublesome and the 

 action so tedious that the method of freezing is but little used for the 

 examination of tissues, except in the laboratory. A freezing micro- 

 tome suitable for the post-mortem room, where the immediate ex- 

 amination of diseased tissues and morbid growths is of extreme 

 importance, is still a desideratum. By substituting the ether spray 

 for the freezing mixture as the cold-producing agent, I have arranged 

 an apparatus in which all the advantages of the freezing method are 

 secured with a minimum expenditure of time and trouble. 



The apparatus consists of a rectangular brass box, through which 

 near to one side passes a brass cylinder provided with a screw 

 piston, in no way differing from that of a Stirling's section-cutter. 

 In the side opposite the cylinder is an aperture in which the glass 

 tube of an ordinary fluid atomizer is inserted. The top of the box is 

 closed by a brass plate hinged in the middle, so that one half forms a 

 lid, through which ether is introduced when the apparatus is used. 

 An exit tube for the vapour is provided in the side close behind the 



