ACETYLENE AS A HEATING AGENT IN CHEMICAL 

 LABORATORIES. 



By Prof. Berthault de St. Jean van der Riet, Ph.D., M.A. 



(Abstract.) 



The author g"a\e some demonstrations of acetylene flames used 

 for heating purposes, the gas being supphed from a generator 

 placed at his disposal by Messrs. Hofmeyr, du Toit and Duffett, of 

 Cape Town. 



It was pointed out that acetylene can be used with advantage 

 in Laboratories where coal gas cannot be obtained. 



On account 'of the gneat heat of its flame however, special pre- 

 cautions have to be taken — wire gauze to be protected by asbestos, 

 and glass vessels cautiously heated. Moreover platinum vessels 

 are apt to become brittle if heated in the most reducing part of the 

 flame. Instead of using acetylene alone it is possible to modify 

 the nature of the flame considerably by the admixture of a small 

 proportion of gasoline (petrol) vapour. The flame then does not 

 'strike back' as easily and the gas may be used under a pressure 

 of only three inches of water, whereas when pure acetylene is used 

 tlie colourless flame is best obtained when the pressure is equal 

 to ten inches of water. This use of gas under comparatively high 

 pressure has certain disadvantages — such as greater leakage, back 

 flow of air into tubes when gas is turned off at night and the like — 

 so that the use of petrol-acetylene has a good deal to commend 

 it. 



SANITARY DWELLINGS.— The third International Con- 

 gress of Sanitary Dwellings is appointed to be held at Dresden 

 from the 2nd to the 7th October, 191 1. The Congress has for its 

 object the scientific advancement of hygiene and sanitation : its 

 work on this occasion will be distributed amongst the following nine 

 sections : — (i) Toiim planning^; building, forms of country settle- 

 ment, garden cities, width of streets, height of buildings : (2) 

 Constructio7i of biiildings ; planning, distribution of space, build- 

 ing material, foundations, basement, kitchens, lavatories, floors 

 and ceilings, staircases, lifts and roofs : (3) Internal arrange- 

 ments ; lighting, heating, ventilation, furnishing: (4) Sanitation; 

 cleaning, removal of refuse, disinfection : (5) Dwelling-houses in 

 towns: (6) Dwelling-houses in the country: (7) Public buildings: 

 school buildings, boarding schools, prisons, hotels, lodging 

 houses, hospitals, convalescent homes, baths, churches, theatres : 

 (8) Workrooms and workshops ; means of communication and 

 transit; railways, tramways, ships, vehicles : (9) Legislation, 

 executive, statistics. 



