COLLECTION OF OBJECTS. 245 



that the muslin should he made removable ; and this may he pro- 

 vided for (as suggested in the " Micrographic Dictionary," Intro- 

 duction, p. xxiv) by the substitution of a wooden ring, grooved 

 on its outside, for the wire ring ; the muslin being strained upon 

 it by a ring of vulcanized India rubber, which lies in the groove, 

 and which may be readily slipped off and on, so as to allow a 

 fresh piece of muslin to be put in the place of that which has 

 been last used. For bringing up portions of larger Plants, either 

 for the sake of examining their own structure, or for obtaining 

 the growths which may be parasitic upon them, a cutting-hook, 

 shaped somewhat like a sickle, may be fitted into the socket of 

 the rod. 



144. The Collector should also be furnished with a number of 

 bottles, into which he may transfer the samples thus obtained. 

 These it will be convenient to have of two kinds ; one set wide- 

 mouthed, and capable of being closely corked, for minute Plants ; 

 the other set with narrower mouths, having short pieces of tube 

 passed through the corks, for the purpose of containing Animal- 

 cules without depriving them of air. The former kind, however, 

 may be safely employed for Animalcules, if they be not above 

 two-thirds filled (so as to leave an adequate air-space), and be not 

 kept long closed. Such bottles should be fitted into cases, in 

 which several may be carried at once without risk of breakage. 1 

 Whilst engaged in the search for Microscopic objects, it is desi- 

 rable for the collector to possess a means of at once recognizing 

 the forms which he may gather, where this is possible, in order 

 that he may decide whether the " gathering" is, or is not, worth 

 preserving; for this purpose either a powerful " Coddington" or 

 u Stanhope" lens ( 19), or a Gairdner's Simple Microscope ( 28), 

 will be found most useful, according to the class of objects of 

 which the collector is in search. The first will answer very well 

 for Zoophytes and the larger Diatomacese ; but the second or 

 third will be needed for Desmidiaceae, the smaller Diatomaceae, 

 and Animalcules. 



1 The bottles in which smelling-salts are now commonly sold, having the corks fitted 

 into disks of turned wood, are very convenient, both in size and shape, for the purposes 

 of the Microscopist ; cases containing 3, 4, 6, or 8 such bottles, are made by Mr. Ferguson, 

 of Giltspur Street. The wide-mouthed bottles with screw caps, made by the York Glass 

 Company, are also extremely convenient. 



