MICRO-BURNERS 
155 
convenient. The usual form employed in blowpipe analysis 
provided with a platinum tip should be chosen and if in addition 
it can be fitted with a hot-blast attachment its usefulness will 
thereby be greatly increased. 
Where the work table is supplied with compressed air a minia¬ 
ture blast lamp of the type shown in Fig. 88 is an invaluable aid 
in fusions, production of high temperatures, preparation of tiny 
blown glass apparatus, etc.; having two joints it can be quickly 
adjusted to almost any position and can even be employed to 
heat material directly under the microscope, although such oper¬ 
ations are best performed by means of an electric current since 
the heat may thus be far better localized. 
Heating preparations while subjecting them to observation 
through the microscope may be accomplished by means of the 
electrically heated hot stage (see page 222) or by a tiny flame 
obtained from a glass or quartz tube drawn out and bent up and 
supported by the substage ring of 
the instrument, the rotating stage 
having been removed to avoid injury 
and the preparation supported on 
an asbestos plate provided with a 
small central orifice for the passage 
of light. It is obvious that when 
moderately high powers and tem¬ 
peratures are to be employed, the 
objectives must be kept cool either 
by means of a strong blast of cold 
air or by water jackets. To meet 
these conditions specially constructed 
microscopes are obtainable; a typ¬ 
ical instrument of this sort is shown 
in Fig. 29, page 71- Fig. 89. Surgical Compression 
Small Tongs. —• As a substitute Forceps. Convenient for Hold- 
for crucible tongs for holding plati- Platinum Cups or 
, . ' Pieces of Foil, 
num foil, cups, etc., a pair of com¬ 
pression arterial forceps. Fig. 89, will be found to be a valuable 
addition to the equipment. Forceps of this sort hold thin 
