Microscopical Society of Victoria. 
105 
tin’s Society by Dr. Johnson some years ago, it was recommended 
as a means to mount Sertularians, Bryozoa, &c., that the objects 
should be boiled in water till all the air is removed, then drained, 
placed for a few hours in carbolic acid, and thence transferred to 
the slide and mounted in balsam. It will be found, however, that 
the water contained in the interior of the specimens being taken 
up by the acid will, unless a large quantity of the latter be 
employed, or the objects be placed in two successive baths of it, be 
sufficient to cause a cloudiness in the balsam. Moreover, it is 
frequently undesirable to lose time by putting the object aside till 
the water and acid Have completely mixed ; and to remedy these 
inconveniences, the object, after removal from the water, should 
be placed in methylated spirits, which will take the place of the 
water in a very few minutes, thence it may be transferred to 
carbolic acid and boiled in it for fifteen or twenty seconds, when 
the object will be ready for mounting at once. I use this method 
with all moist specimens, and find it of great advantage in 
enabling me to mount them without delay, besides which, the 
quantity of acid used or spoiled is comparatively small, its place 
being partially filled by the inexpensive methylated spirit. 
(4.) Dust in Canada Balsam .—I have often found it difficult to 
obtain balsam perfectly free from foreign particles, and now 
always keep two bottles. One is filled with balsam made quite 
fluid by the addition of benzine or chloroform, which is well stirred 
up with it. This stands undisturbed while the other bottle is in 
use, a period of several months, during which all particles sink to 
the bottom. When the other bottle is finished this is brought 
into use, the first bottle being cleaned out, filled with thinned 
balsam and stood aside in its turn to settle. This mixture will 
usually require to be somewhat thickened by evaporation before 
using- When balsam thus prepai*ed has stood for some months, 
the bottom of the bottle will be seen on holding it up to the light 
to be covered with a very fine dust which has settled from the 
balsam, and if it be compared under the microscope with most 
fresh samples its superior clearness will be at once apparent. 
