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portion was made of gun metal to ensure greater stability, 

 whilst the upper part was of aluminium. 



The President said it would be obvious that by making the 

 lower part of a heavier metal the centre of gravity would be 

 lowered and the steadiness consequently increased. 



Mr. Goodwin exhibited a small microscope lamp, in which 

 the chimney and reservoir were of metal. The chimney had 

 two apertures, one closed by a coloured glass and the other by 

 a piece of plain glass, either of which could be used by turning 

 the lamp round. The weight of the lamp was only 3ozs., and 

 though so small it was quite powerful enough for ordinary use, 

 and held enough paraffin to burn about three hours. He found 

 that for the wick nothing answered better than a piece of folded 

 blotting-paper. 



Mr. Karop inquired if the pieces of glass were turned into the 

 metal of the chimney ? 



Mr. Goodwin said they were fitted into a small ring cap. 



The President thought this was a charming little lamp ; he 

 suggested, however, that it would be improved by making the 

 glass-covered apertures long shaped instead of round, so that a 

 microscope could be worked direct without a mirror. 



Mr. Ingpen thought the idea of using blotting-paper as a wick 

 was an extremely good one. He had tried several thicknesses 

 of tape with some success, but thought the blotting-paper likely 

 to answer better. 



The President said there was a new lamp just coming out, 

 which was fitted with a carbon wick, one of the most extra- 

 ordinary things about which was that if it was held at an angle 

 of 45° it went out, so that under these conditions it was really a 

 self-extinguishing lamp. Whilst on the subject of lamps, he 

 might mention that the best he had ever met with was the Hitch, 

 cock mechanical lamp, which burnt without any chimney, the 

 draught being supplied by the rotation of a rapidly revolving 

 fan. It was supplied with a patent feeder, with which it could 

 be filled without any risk of pouring over or of soiling the 

 fingers, and the light it gave was most extraordinary; the wick 

 was less than lin. wide, and as compared with one of Hink's 

 duplex lamps the light was in the proportion of 14 to 18. It 

 would be a great thing if they could get a lamp on this principle 

 small enough for microscopical purposes. 



