No. 3201 Massive Microscope.

The Massive microscope was designed to provide an instrument for the use of research workers, which by reason of its great rigidity and accuracy of construction, would enable the full advantage to be taken of the latest forms of high power object glasses, achromatic condensers and dark ground illuminators, which have reached a very high standard, and which therefore require similar perfection in the mechanical adjustments of the microscope upon which they are used. This rigidity of construction allows for the interchange of the object glasses and substage apparatus, without any danger of disturbing the adjustments, so that the change over from transmitted to dark ground illumination can be made rapidly and without incurring the necessity of any general readjustment of the microscope. The advantages of such an instrument, in the saving of time and in the high order of performance obtained will readily be appreciated. For such work as photo-micrography this great rigidity is also of the utmost benefit.

The following is a brief description of the main constructional details.

The limb consists of a massive brass casting which extends in one piece from the body to the mirror. The tail piece and slow motion slide are planed out in one continuous cut to ensure perfect alignment of the substage and focussing slides. The stage is rigidly fixed to side wings which form an integral portion of the limb. The base and pillar supporting the limb are heavy and so designed to render the instrument equally rigid in all positions. The back of the foot of the microscope carries a short vertical post to take the weight and form a rigid support when the microscope is in a horizontal position.

The fine adjustment is exceptionally delicate; each division on the milled head moves the body -001 m/m. The coarse adjustment milled heads are very large, enabling an accurate setting to be made.

The stage measures 4|x4§ inches. It is flat with a gap cut out in front to enable substage apparatus to be readily changed without altering the focussing adjustments. The mechanical stage, which fits into dovetails cut in the flat stage, has specially delicate motions actuated by milled heads which project from the right hand side. The cross slide has a travel of 3 inches and the vertical slide has a travel of 1£ inches. Vernier scales are provided to both movements, and a clamp is attached to the vertical motion.

The substage has rack and pinion focussing and centring adjustments and has a tubular fitting of the standard (R.M.S.) size. Its upper surface has an additional dovetailed fitting to receive apparatus. Substage condensers and dark ground illuminators are mounted in dovetailed fittings, held in position by a clamping milled head. These are accurately centred and are of the same height so that the}^ can be rapidly changed while the object is under observation, the gap in the front of the stage permitting this to be done without the focus of the substage being altered. The tubular portion of the substage is free to receive other apparatus which can be used in conjunction with condensers and illuminators.

The body is of 2 inch diameter, with a drawtube giving a variation in length from 140 m/m. to 200 m/m. A rack and pyiion double extension drawtube, as illustrated on page 30 can be fitted if desired. A high power binocular eyepiece can also be fitted to the instrument.

The microscope is packed into a solid mahogany cabinet.

In many laboratories employing a large number of microscopes, a small proportion of the equipment consists of Massive microscopes which are used for the most exacting work.

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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 99,26 %.

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

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