Microscope Eyepieces.

BECK.

No. 3259

No. 3259. Comparator eyepiece ... ........ ... ........ ... £10 10 0

This eyepiece is for use with two microscopes, for giving in one eyepiece, the images in each microscope combined into one field of view for comparison purposes.

No. 3273. Erecting eyepiece ... ... ... ... ... ... ... ... £2 0 0

This is a compound eyepiece for use with a 1 6m/m (f inch) object glass. With this object glass it gives a magnifying power 10 to 40 diameters by extending the drawtube and a very large field of view. It gives an erect instead of an inverted image and is particularly useful for dissecting.

No. 3276A

No. 3276A. Cobweb eyepiece micrometer ...................... £9 0 0

This eyepiece has two cobwebs, one of which is fixed and the other is movable by a micrometer screw. The screw has a millimetre pitch and a drum divided into 100 parts, each division reading 1 /100 millimetre. The saw-shaped scale of teeth is so arranged that each tooth is equal to one turn of the screw.

No. 3257

No. 3275. Beck micrometer eyepiece ..................

This consists of a complete eyepiece with a magnifying power x 8, and a special vernier millimetre scale placed in its focus.

It is provided with a collar which fits over the drawtube and can be clamped in position by a milled head. The eyepiece has an adjustment for focussing the scale.

The scale (see diagram) is in millimetres with a vernier reading to 1 /10th of a m/m. On the left is a vertical series of divisions divided in half millimetres for rough measurement. For fine measurement the object to be measured is placed in a horizontal position, and is measured to 1 /10th m/m. by use of the slanting

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line on the right. The image of an object as shown in the diagram measures 3-25 m/m., because it covers three large divisions and extends to the oblique line at a point halfway between the -2 and *3 of tenth millimetre vernier divisions.

To obtain the actual size of the object itself this result has merely to be divided by the initial magnifying power of the object glass.

No. 3256. Ehrlich eyepiece ......................................... .. £3 10 0

This is a Huyghenian eyepiece of standard sue and power X 6 and provided with a square aperture, the size of which can be varied from 1 to 8 m m. It is useful for measurement of areas or for blood counting.

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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 97,71 %.

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

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