78 Guy J on Preserving Microscopic Objects in Tubes. 
ten on the card in front, or on the label behind. 2. Or_, using 
a card of the same size and shape, with the same central 
circular opening, this opening is enlarged by two smaller 
openings of the same shape, one on each side, which openings 
are made to touch the central opening, or are somewhat sepa- 
rated from it, according as the tube is shorter or longer, the 
three apertures being joined by cuts made with a penknife or 
chisel. An oblong strip of gilt paper is then gummed at the 
back, and the tube, made to rest upon it, is fastened in its 
place by a similar label in front. The openings being made 
near one margin of the card, room is left beneath for a de- 
scription of the object. 3. If we prefer the common glass 
slide to card-board, the three openings, joined together as be- 
fore, are punched out of a small oblong piece of card-board, 
the card-board is gummed to the slide, or, better, to an oblong 
piece of coloured paper, perforated like the card-board itself, 
gummed to the glass ; and the glass tube is then secured in 
the card-board and upon the slide by a coloured slip of paper 
projecting beyond the card-board, so as to fix it more firmly 
to the glass. A similar arrangement of a perforated card, 
bound down by slips of gummed paper to the surface of the 
glass, will enable us to examine the contents of the tubes 
before mounting them. 4. There is also a very simple method 
of mounting the tubes so as to submit them to immediate 
examination. Tt consists in separating the layers of the card- 
board, furnished as before with a circular central opening at 
the edges of the card, and inserting the tube between them. 
The tube, after being examined and adjusted, may be secured 
in its place by an edging of gummed paper, and the card may 
then be labelled and ornamented if required. 5. There is 
still one other mode of mounting these small tubes. The 
card-board is first indented with a groove running in the 
centre line of the card and in the direction of its length. 
Around this groove a black band is rubbed in with a stencil- 
plate ; the tube is then dropped into the groove and secured 
in its place by two narrow strips of gilt or coloured paper. 
If the object is to be examined by transmitted as well as by 
reflected light, a small circular hole may be punched in the 
centre of the card and of the black band. 
The specimens to which I referred at the beginning of this 
paper were such as would have to be used for the instruction 
of a class of pupils ; and I may, therefore, take this opportu- 
nity of indicating the easiest method of rendering these tubu- 
lar specimens available for class-teaching. 
For this important purpose it is necessary either to resort 
to a costly arrangement for circulating the ordinary micro- 
