382 ANNUAL RECORD OF SCIENCE AND INDUSTRY. 



too narrow, the lower end of the candle is. to be held over an- 

 other burning candle, and the part melted off allowed to drop 

 into the socket as before, until sufficiently reduced in size, 

 when it is to be set into the melted liquid as in the former 

 case. Candles thus treated can be allowed to burn down 

 completely in their sockets without involving any danger 

 from burning paper or other material used as a wrapping. 

 15 C, xiv., 221. 



RESTORING CRACKED PORCELAIN DISHES. 



Porcelain dishes which have become cracked may, it is 

 said, be rendered water-tight again by drying them complete- 

 ly in a warm place, after which a solution of water-glass is to 

 be poured in and allowed to stand overnight, then pouring 

 it off and allowing the adherent film to dry slowly. 5 C\ 

 1871,ii., 16. 



preparation of wooden labels for plants. 



Wooden labels for plants to be inserted in the ground 

 may, it is said, be preserved for an indefinite time by first dip- 

 ping them into a solution of one part copper vitriol and 

 twenty-four parts water, and subsequently immersing in lime- 

 water or a solution of gypsum. 6 C, July 14, 282. 



BORAX FOR EXTERMINATING COCKROACHES, ETC. 



Among the many applications of borax recently made, one 

 of the latest is in the extermination of cockroaches, which 

 purpose it is said to answer very perfectly, although we are 

 inclined to doubt it. Half a pound, finely pulverized and 

 scattered about where these disagreeable pests frequent, will, 

 it is said, clear an infested house so thoroughly that the ap- 

 pearance of one in a month is quite a novelty. It is not 

 known upon what peculiar influence of the borax this de- 

 pends ; but we are assured that the facts are as stated. One 

 advantage of this application is the harmless nature of the 

 borax, so that there is no danger to the household from its 

 being exposed. The use of borax in Europe for washing is 

 well known, the addition of a large handful of borax, instead 

 of soda, to ten gallons of water, being sufficient to save half 

 the quantity of soap ordinarily required. For light fabrics 

 and cambrics a moderate quantity is to be used ; but for 



