Microscopes and Accessory Apparatus Part 13

(The same, adjustable =$45.--=.)

Lamp and rheostat are furnished at factory prices. In ordering it is well to state the strength of the available electric current, also whether it is constant or alternating.

=Outfit for projection of lantern slides:=

Metal-base with optical bench, triple collecting lens (adjustable) of 150 mm aperture; large cooling cell; slide carrier with bellows; triple revolving arm, with rack and pinion adjustment =108.--=

Projection objective of 300 mm focal length =20.--=

(A second objective of same focal length may be slipped over the former, the two combined represent an objective of 150 mm focus. Additional price =$20.--=.)

=Outfit for microscopical projections:=

Cylinder-diaphragm and condenser; objectstage and small cooler with moveable slide-holder. Objective carrier with triple nose-piece: rack and pinion adjustment and micrometer-screw. Broad tube with Iris-diaphragm into which the smaller draw-tube fits. Two projection eye- pieces.

Object-stage and objective carrier are provided with hinges. Wooden cover with cloth curtain =84.--= Transport =250.--= -------- Complete outfit =334.--=

118. =Megascope=, apparatus for the projection of opaque objects; special offers will be made on application.

119. =Attachment for spectroscopic examinations=, to be used on the optical bench and in connection with the lamp of the projection apparatus No. 117. Slit mechanism, large triple prism, object-stage =80.--=

120. =Large projection apparatus=, of special design with latest improvements, for lantern slides size 1318 cm, for micro-projection, and megascope attachment.

Special offers for this apparatus will be made on application.

(In ordering it is necessary to state the voltage of the available electric current, also whether it is direct or alternating.)

121. =Trichinoscope.= Simple electric lamp (hand feed) of 20 Ampere, mounted on adjustable stand, encased in Russian iron box, double collecting lens (adjustable) of 120 mm Aperture, with condensing lens.

Mechanical stage for gla.s.s compressors, with movements at right angles to each other, cooling cell for the preparation with a continual flow of cold water.

Objective carrier with micrometer screw, wide tube with Iris diaphragm =120.--=

Projection objective of 35 mm focus, aperture f:3,5, with Iris diaphragm =18.--= -------- =138.--=

[Ill.u.s.tration: Trichinoscope No. 121.]

=Microtomes.=

[Ill.u.s.tration: Large Sliding-Microtome.]

Our larger microtomes are heavy and all their adjustments are of the most accurate construction, the result being that they are very steady when in use and permit the cutting of very thin and uniform sections.

They are to be had in three different sizes. The larger two are slightly different in construction from the third. The two former microtomes are provided with an automatic feed attachement. A heavy knife-carrier slides smoothly and rapidly on a horizontal track and is so arranged that it may be manipulated by the hand of the operator alone or by a wheel and chain device, which tends to a.s.sure a perfectly uniform stroke of the knife.

The objectclamp is raised vertically by a micrometer screw. This motion is accomplished by turning a large disc having teeth cut into its periphery and a turn of one tooth being equal to an elevation of 0.0025 mm.

The automatic feed is arranged as follows: With each return of the knife-carrier to the end of its track pressure is made upon an adjustable lever which regulates the motion of the micrometer wheel.

This device may be so adjusted as to move the micrometer disc any number of teeth from one to ten with each sweep of the knife.

Three different forms of clamps may be had for these microtomes, and freezing apparatus as well as paraffin tables can also be fitted.

The Fixed clamp, No. 128, represented in the figure of the large sliding microtome, serves to clamp the specimen in position and does not allow any further adjustment.

The Ball and Socket clamp permits the adjustments of the specimen after it is held in the clamp by means of a ball and socket joint--see figure of No. 129--a set-screw then holds it firmly in position.

The Naples clamp permits the accurate adjustment of the specimen at any level, the clamp being supported on two horizontal axes at right angles to each other, the one controlled by rack and pinion, the other by endless screw.

The knife-carrier is arranged to hold the Thoma form knives, which are fastened by means of a wing-screw. Other knives require a special holder, such as No. 139.

122. =The Large Sliding Microtome= has a track 42 cm long. Its price with automatic feed attachement, wheel and chain arrangement for the knife carrier, and fixed clamp, without knife =62.--=

123. =The same=, with knife holder for Jung microtome knives =66.--=

124. =The same=, but without the wheel and chain arrangement for the knife carrier =50.--=

125. =Medium size Sliding Microtome=--Track 32 cm long; automatic feed attachement; wheel and chain motion of knife carrier and fixed specimen clamp--without knife =56.--=

126. =The same=, with knife holder for Jung microtome knives =60.--=

127. =The same=, but without wheel and chain motion =44.--=

128. =Fixed Specimen Clamp= =4.--=

129. =Ball and Socket Clamp= =6.--=

130. =Naples Clamp= =12.--=

[Ill.u.s.tration: Ball and Socket Clamp No. 129. Naples Clamp No. 130.]

131. =The Support-Microtome= has a track 19 cm long. The knife-carrier slides on a double f.l.a.n.g.ed support and is moved by means of a large k.n.o.b. The motion is smooth and quick. The specimen is held in a clamp supported on two adjustable axes at right angles to each other, thus permitting its adjustment in any position. The specimen carrier is moved vertically by means of a micrometer screw to which a large disc is attached. This disc is graduated, each degree representing a motion of the specimen carrier of 0,005 mm. The price of this microtome with knifeholder No. 139, without box or knife is =34.--=

[Ill.u.s.tration: Support-Microtome No. 131.]

131a. =Small Sliding Microtome=, length of bed 21 cm, heavy knife-carrier, object clamp for specimen 25 mm diam., micrometer screw with disc graduated into 100 degrees, each division representing a motion of 0,005 mm. Price including knifeholder No. 139, without knife =24.--=

[Ill.u.s.tration: Small Sliding Microtome No. 131a.]

=Microtome knives.= (Made by W. Walb.)

=A. Thoma's Model=, plano-concave, with handle adapted for clamping immediately to the knife carrier of the microtome, in box.

[Ill.u.s.tration]