is also provided with two short tubes for the inlet and outlet of liquids or gases. Observation is made through a thin disc of quartz mounted in the middle of the cover.

If desired, the Ultra Condenser can be supplied with provision for producing electric sparks within the substance under examination. In this case the Ultra Condenser is supplied with an additional cover of ebonite fitted with terminals and two platinum electrodes reaching to the centre of the chamber.

The above illustration shows a convenient arrangement of a microscope with the Ultra Condenser attached. The condenser outfit includes a glass vessel with stand, a pinch cock and tubing for passing liquids into and out of the hollow chamber.

No. £. s. d.

114. Ultra Condenser with Glass Vessel, Holder, and

Pinch Cock ............................4. 0. 0

115. Ultra Condenser with Sparking Device..5. 0. 0

Artificial Sources of Light

for use with the microscope.

Luminescence Lamp. This lamp furnishes a beam of light which contains ultra-violet rays only and is used for the observation of fluorescent substances. The apparatus consists in the main of a Liliput Arc Lamp taking a current, of 5 amperes, a condensing lens made of a material which transmits ultra-violet light, and U. V. light filter the function of which is to absorb the visible rays and transmit none but ultra-violet radiation and at the same time give rise to less heat than ordinary carbons,

The entire lamp is contained in a light-proof casing, in such a way, however, as not to interfere in the slightest degree with the perfect regulation of its function.

It is advisable to perform all work with the Luminescence Lamp in a darkened room.

The U. V. filter derives its peculiar efficacy from the use of nitrosodimethyl anilin. To eliminate the last traces of red light the filter trough should be filled with a 20 °/o solution of copper sulphate with the aid ot the two funnel tubes supplied with the apparatus; this solution serves the additional purpose of acting as a cooling

Codeword

Ultraismo

Ultrato

16

---

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 99,31 %.

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

---