45, CORNHILL, B.C., AND 122, BEGENT STREET, W., LONDON. 501 



3101 Patent Metallic Thermometers (Immisch's Patent), for Clinical and ordinary 



uses (fig. 3101). 



The chief advantages that this instrument has over those in ordinary use are 

 its convenient shape and size like a miniature watch, the readiness with which 

 the temperature may be read off, and its comparative freedom from liability to 

 in injury. It is sensitive and accurate. No shaking down being required, the 

 instrument readily accommodates itself to altered temperatures. About 30 seconds 

 elapses before the temperature last recorded is changed. This space of time is 

 generally admitted to be sufficient to allow the Thermometer being taken to the 

 light and its indications noted. These Thermometers are divided to both Fahrenheit 

 and Centigrade Scales. 



Pi-ice in neat Leather Case, Silver, 1 Is.; Gold, 2 10 



3102 Hygrometers, for Hospital Wards, &c., 14s., 21s., fig. 3102, see also page 73. 



3103 Bath Thermometers, with Dr. Forbes' specifications, in japanned Metal 



Cases, 5s. 6d,, 6s. 6d. (fig. 3103). 



3104 Chemical, Bath and Ward Thermometers, for particulars of various sizes and 



prices, see pages 153 and 159, and figs. A, B, and B*, next page. 



3105 Thermometers for Drying Rooms and Hot Water Apparatus, see page 167. 



3106 Disinfecting Thermometers, of various forms and size, as supplied to 



Government hospitals and other public institutions, see page 169. 



3107 Improved Dropping Bottles, for Solutions of Nitrate of Silver, Acids, or other 



Medical Preparations, &c., &c., (see page 192, fig. 449). 



These bottles made of glass, the stopper, which is carefully ground in, being 

 formed of stout barometer tube drawn out to a point ; over the stopper and neck 

 is fitted a glass cap, also ground so as to be air-tight. The bottle being about 

 two-thirds filled with the fluid to be used, is held in the hand inverted (the cap 

 having been removed, when the warmth of the hand will expand the confined air, 

 and expel the fluid through the perforated stopper, drop by drop. These Dropping 

 Bottles have been found very useful both for Medical, Chemical, and Photographic 

 uses. Price Is. 6d. each, or in turned wood pocket case, 3s. 



3108 LOWE'S TEST FOB SEWAGE IMPUBITT IN WATER. 



Mode of using the Test. Break one of the glass balls by dropping it from a 

 height of a foot into a clean wine glass. Fill the wine glass with the water to be 

 tested. 



The more dangerous kinds of impurity ammoniacal products derived from 

 sewage if present in considerable amount, are at once detached, by the production 

 of a yellow colour, or by a flocculent deposit, which becomes yellow or greenish 

 after standing six hours (the glass being covered to exclude dust). Water of this 

 description is unfit for use. If a copious white precipitate forms, or if any cloudi- 

 ness ensues, the water should be submitted to analysis, and should in no such case 

 be drunk without previous boiling. 



If the water remains perfectly clear it may be used with safety. 



Price, 2s. 6d. per dozen. 



The greatest care should be taken that the wine glass, containing the test and broken 

 glass, be emptied after using, and thoroughly cleansed, the Test being poisonous. 



