202 Transactions of tlie 



II. It is of consequence that objects allied to each other should 

 not, on feeble grounds, be placed far apart. 



III. Keep as much as possible to a uniform style of nomen- 

 clature and size of slide, whenever the specimens admit of such. 



IV. Endeavour to obtain good typical specimens, and see that 

 they are in a sound state of preservation before finally giving them 

 a position in the cabinet. 



V. Eeject all lumber, kept with the idea that numbers add to 

 the value of a collection ; whereas they rather weaken its usefulness. 



These broad rules of guidance or general principles being ad- 

 mitted, it seems that the ultimate end of system in dealing with 

 natural objects— and this is especially applicable to microscopic 

 textures — is tlie attainment of a comprehensive grasp of the affinities 

 and structural relations of things. 



Around us everywhere matter exists in an infinity of forms, 

 organic and inorganic. Materials building up organs adapted to 

 perform functions ministering to the life and well-being of animals, 

 or perchance supporting and maintaining vegetable organism. 

 Materials wherewith minerals and precious gems are constructed, or 

 elementary constituents out of which the chemist transforms sub- 

 stances applicable to the arts and sciences. In other words, the raw 

 material of all useful and ornamental products, such as food, clothing, 

 and microscopic art ; also earthy substances of whatsoever kind, 

 and intimate stinictures and organs of all vegetables and animals, 

 recent and fossil. Indeed, everything likely to be examined by the 

 microscope or retained as a preparation or interesting object in a 

 histological collection, reduces itself within limits, when the ele- 

 mentary composition is unravelled. This limit is its primary 

 textural component parts ; and therefore this forms one kind of basis 

 of classification to start from. 



As, however, the simple elementary parts reconstruct them- 

 selves in a variety of ways into tissues and organs, and these tissues 

 and organs again develop themselves so as to constitute systems ; 

 and as the systems are exponent in a great measure of the types of 

 construction of vegetables and animals, we have in these so-called 

 systems, normal and abnormal, a gauge wherein to measure and 

 compare structural differences of two of the kingdoms of nature. 



The third or inorganic kingdom comports itself more as to 

 chemical composition, or the manner in which the masses are 

 aggregated ; so that instead of systems of organs, we have groups 

 of substances to deal with. 



Lastly, microscopic optical apparatus, art-microcosms, &c., are 

 associated according to use, or whenever the subject agrees in 

 bearing. 



I mentioned that naturally the primary elementary tissues lead 

 to a basic series, whereon a classification might be taken to start 



