450 XXXII. CELL-DIVISION AND NUCLEAR DIVISION. 



large cover-glasses, so that the band need not be cut into two 

 snort sections. If the band should be somewhat crumpled, it can 

 be laid on the back of the hand, and drawn with the needle 

 towards one end. The warmth of the hand and the slight 

 resistance which it offers facilitate the straightening of the band. 

 It is now necessary to fasten the paraffin sections, or series of 

 sections, upon the object-slide. We can do this either with water, 

 or with glycerine albumen, or with a combination of both methods. 

 Pure dust-free water is slightly warmed in a shallow porcelain 

 dish, and the sections placed upon this with the needle. They 

 spread out on this water very beautifully, and are lifted out of it 

 by the object-slide being pushed underneath. They are then 

 allowed to dry in the air, and laid for about an hour or longer 

 on a shelf of the upper case of the paraffin oven figured on page 

 448, or else in a warm chamber. The paraffin is afterwards 

 dissolved in turpentine or xylol, while the sections of the object 

 remain adhering to the object-slide. If fixing to the object-slide 

 with glycerine albumen is preferred, a mixture of equal parts egg- 

 albumen and glycerine' is used, the solution being filtered. If a 

 piece of camphor is put in, it will keep for some weeks. It is 

 placed on the object-slide in only very small quantity, and rubbed 

 smooth \vith the ball of the hand, forming thus an unrecognisable 

 layer. The sections are now laid on it, and pressed with a dry 

 camel-hair brush, or the dry finger, or a quite dust-free piece of 

 rag. The object-slide is then warmed over a flame till the paraffin 

 begins to melt, and this latter is then removed, just as in the 

 other case, with turpentine or xylol. The combinations of the 

 two methods consists in rubbing the glycerine-albumen on the 

 object-slide, and then pouring on a little warm distilled water. 

 On this water, which may again be slightly warmed, the sections 

 are floated and arranged, and after they are properly spread out, 

 the water taken up with blotting-paper, the preparation dried in 

 the air and warmed over a flame. It has also been advised, after 

 rubbing on the glycerine-albumen, to coagulate the albumen in 

 the warm chamber at about 70 C., then pour on the water, 

 transfer the sections, and warm the water slightly until the 

 sections have spread out quite smoothly. Then remove the 

 water with blotting-paper, and dry the preparation in air or in 

 a warm chamber at about 30 to 35 C. Similarly pure albumen 

 has been used. This is shaken up for a considerable time with 

 ten times its bulk of water, filtered, spread out on the object-slide 



