thin glass plate inclined at an angle of 45° and which attaches by a clamping ring to the objective mount, as shown in Fig. 1.

The Vertical Illuminator proper, as designed for use with high power lenses from No. 3 up to and including oil-immersion lenses, is shown in Fig. 2. It consists of a cylindrical body with an upper screw thread for attachment to the microscope, whilst the lower one receives the objective.*) In front, the cylindrical portion of the body is fitted with a short tube within which moves a draw-tube fitted with a condensing lens. On the right the cylindrical casing has a rectangular aperture for the insertion of small interchangeable and movable slides. One of these carries a totally reflecting prism, the other a spring clip for the attachment of a mica plate.

The Mirror and Lens Stand. (Fig. 3). Is mounted on a heavy iron foot from which rises an upright iron rod having a circular disc attached to it by a sliding fitting. At the centre this round disc is fitted with an immovable mounted plano-convex lens L2 and in front of this lens is an iris-diaphragm I, by means of which the pencil of light transmitted through the lens may be diminished as may be required in any given case. At the back of the disc the frame carries two mirrors Si and S2. Of these the lower one is fixed at an angle of 45°, whilst the upper mirror above the lens L2 can be folded down. When not in use, this mirror will occupy the position S3 indicated by dotted lines.

For accurately centring the condensing lens L2 with respect to the optic axis of the Vertical Illuminator the disc is fitted with a finely cut screw.

Each apparatus is supplied with detailed Directions.

No. fe s. d. Codeword

106. Reflecting- Plate Holder . ...........................0. 5. 0 Opaeabam

107. Vertical Illuminator, for use with high power objectives with two interchangeable slides, one being fitted with a prism and the other a reflecting plate holder

to carry a plate of mica. In case......................2. 5. 0 Opaeabis

108. Mirror and Lens Stand, consisting of a large (screen disc with fixedly mounted condensing lens, iris-diaphragm

and two movable mirrors ...............................1. 5. 0 Opaeamus

109. Vertical Illuminator with Mirror and Lens Stand . . 3.15. 0 Opaea

*) For use with the Vertical Illuminator we supply objectives from No. 3 upwards in special short mounts.

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Le texte affiché peut comporter un certain nombre d'erreurs. En effet, le mode texte de ce document a été généré de façon automatique par un programme de reconnaissance optique de caractères (OCR). Le taux de reconnaissance estimé pour cette page est de 98,83 %.

La langue de reconnaissance de l'OCR est l'Anglais.

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