ei-^ 



Popular Science Monthly 



Systematic Control of Water in a 

 Bath Tub 



A RESIDENT of a small city, wishing 

 to eliminate the final sponging with 

 clear water, necessary to remove the pre- 



TWIN 



PLUGS ^<«^-le:ad pipe: 



Two overflows at different levels in 

 the bath-tub, opposite to the faucet 



viously applied coating of soapy liquid, 

 decided upon this method of keeping the 

 water constantly clean. As the ten- 

 dency of the water was to carry the soapy 

 matter to the end farthest away from the 

 bath overflow, two overflows and plugs 

 were fitted at the opposite end, thereby 

 providing for two water levels. Regu- 

 lating the flow of water from the bibbs, 

 the bather was able to keep the unclean 

 water constantly moving out of either of 

 the two overflows. — James M. Kane. 



A Cement for Firmly Holding 

 Glass on Metal 



ONE of the best cements for joining 

 glass to other substances consists'of a 

 mixture of gum arable and calomel. Its 

 adhesive power is great. It is prepared 

 by putting the very best and purest gum 

 arable into a small quantity of water, 

 and allowing it to stand overnight so 

 that it attains a glue-like consistency. 

 Calomel, or as it is sometimes called, 

 mercurous Chloride or subchloride of 

 mercury, is added in a sufficient quantity 

 to make the mass a trifle more sticky. 

 The ingredients are thoroughly mixed on a 

 glass plate with a spatula. Calomel is a 

 poison, so no more should he made than is 

 required for immediate use. This cement 



hardens in a few hours, but the most 

 satisfactory results are obtained when it is 

 permitted to stand for one or two days. 

 To insure a very serviceable cement it is 

 necessary to utilize only the best materi- 

 als, as inferior grades are useless. Another 

 excellent glass cement is made from gum 

 mastic, powdered isinglass and alcohol. 



Fastening Cases to Railing in 

 Historical Museum 



THE method used in placing the 

 manuscript cases in the Historical 

 Society building in a small city is shown 

 in the illustration. It is a good example 

 of economy in space. The gallery running 

 around the upper section of the library 

 room has a pipe railing to keep the 

 clerk from falling off to the lower floor. 

 The upper rail has been utilized to 



&16S5 



A glass case holding manuscript for 

 exhibition on the guard rail of a gallery 



hang cases containing valuable manu- 

 scripts. The framework of the case is of 

 flat iron, the back ends of the top being 

 curved so as to hook over the upper 

 pipe rail. 



By using this method the manuscripts 

 are perfectly safe, they are in a good light, 

 and it is possible to examine each one by 

 itself.- James M. Kane. 



