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 13×18 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 Ampère, mounted on adjustable stand, encased in Russian iron box, double collecting lens (adjustable) of 120 mm Aperture, with condensing lens. Mechanical stage for glass 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.--= [Illustration: Trichinoscope No. 121.] =Microtomes.= [Illustration: 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 assure 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.