ANDREAS KURTZ 125 



No 4. Dr. Ure found in good powder: 



Chlorine 36 



Lime 28 



"From Gray's 'Operative Chemistry,' page 

 436, a chamber from pitch and Paris plaster 

 is made, 12 feet long and 2 feet wide, of 

 bricks, and numbers of shelves, filled with 

 fresh slaked lime, 4 days are usually required 

 to impregnate the lime with the gas to 

 saturate it well, the layers of lime are 

 generally very thin, say half an inch thick, 

 and when this is saturated another layer is 

 put upon it, and so on, they can see by the 

 colour of the powder whether it is quite 

 saturated. The mixture recommended by 

 Gray, page 437, is 3 of manganese, 8 of 

 common salt, 6 of sulphuric acid, and 12 of 

 water." Then he has sketches, and makes 

 what appears to be suggestions of his own : 

 He does not see why the chambers should 

 not be increased in size and that the apparatus 

 might possibly be worked with advantage by 

 a fan. Of course, these references have only 

 a historical interest. 



We must now come to his work in Man- 

 chester. A date is given that may serve as 

 a starting point. 



