1897] MICROSCOPICAL JOURNAL. 27 



any itarlicular position mav be recorded and found aj^ain 

 easilv. The object is in a simple carrier close to the sur- 

 face of the stag-e. The mechanical stag-e can be fitted to 

 any stage if the location of the clip-holes and center of the 

 stai^e is known. It is sold by Zentmayer for S16.00. 



MICROSCOPICAL MANIPULATION. 



To Distinguish Guaiacol from Beechwood Creosote. ^ — 

 Mr. Vreven utilizes the following- method for disting-uish- 

 ing- l)eechwood creosote from liquid g^uaiacol: He places a 

 few drops of the substance under examination in a test 

 tube and adds 2 or 3 drops of ether and 1 or 2 drops of con- 

 centrated nitric acid or of concentrated hydrochloric acid 

 and ag-itates the mixture. There is first of all a reddish 

 brown coloration produced in the ethereal layer. After 

 spontaneous evaporation of the ether there remain oily 

 drops if the substance on examination is creosote, or if it 

 is licjuid g-uaiacol the residue is in the form of crystals. 

 Sometimes crystals are not produced even if the substance 

 examined is liquid gfuaiacol unless the residue is ag^itated, 

 but upon agitation the crystals appear immediatel}'. Under 

 the same conditions carbolic acid also yields crystals, but 

 their form does not at all resemble the form of crystals 

 produced by g-uaiacol, the crystals of the latter consisting- 

 of needles ag-g-reg-ated in the form of stars which are very 

 easily disting-uished under the microscope. — American 

 Drug-g-ist. 



New Method of Purifying Water. — The French Acad- 

 emy of Sciences appears to indorse the new method of 

 purifying- water by calcium permang-anate and mang-anese 

 dioxide. According- to this method, the calcium perman- 

 ganate coming- in contact with organic matter and micro- 

 org-anisms, destroys them and decomposes itself into oxy- 

 g-en, mang-anese oxide and lime ^IMien, to carry off the 

 surplus of permanganate and comjtlete the purification, 

 the water is p(jured over managanese dioxide; oxyg-en in 

 the nascent state is thus freed and it ]:)urns up any remain- 



