PROCEEDINGS OF THE rOLYTECHNIC ASSOCIATION. 439 



Cv)1ovs are dissolved iu alcohol and diluted with water, not too hot. into 

 which tlie feathers are plnng'ed. After being- completely dyed they are 

 removed from the batli, washed and dried. Tliej' are then curled by 

 means t)f a well polished bone knife. 



Anti-corrosive Mixture. 



A solution of beeswax in benzole will prevent steel from rusting. A 

 thin coating of wa.x will stick to the object imbued witl^it, while the ben- 

 zol(> evaiiorates. 



Destruction of Bookworms. 



In {he Hodleian Library the insects belonging to the peinida? species — 

 small-sized beetles of whicli there are three species— are found not oidy to 

 attack books but to burrow in the wood carvings. They have been effec- 

 tually destroyed by means of the vapor of benzine or benzole. It is essen- 

 tial that the rooms in which saucers of benzole are placed should be as 

 nearly air-tight as possible. The application shotdd be made in the spring, 

 and as the ova of these insects are not all developed within one year, it is 

 necessary' to repeat the operation during the next spring to ensure their 

 extermination. 



Development of Wheat. 



M. Pierre is continuing his investigations of the development of corn. 

 During nineteen days of observation extending from July 6th to July 25th 

 of the present year, he found the whole ear gained eighty per cent in 

 weight, while the stalks and husks were undergoing a dinunution in weight. 

 The mineral substances in grain during this term decreased in weight 

 nearly one-fifth, while nitrogen increased nearly one-seventh. M. Pierre 

 believes the grain is nourished at the expense of the upper portions of the 

 stem. 



Dr. Rowell remarked that a lady had noticed that one grain of rye pro- 

 duced twelve hundred grains. 



Refuse Corks. 



The scavengers of Paris gather from the sewers corks which have been 

 used and thrown away, and sell them to persons who make it their busi- 

 ness to tcvivtJ them. Some are recut, others retaining their original shape 

 are CQvered with a powder which gives them the color of new cork. The 

 holes in them arc filled with mastic. Formerly these corks were sold only 

 to makers of ink and blacking, but lately they have been used by the re- 

 tailers of bottled beverages, such corks being bought for about one dollar 

 and thirty cents per thousand. 



The question has been raised whether there is not danger in this prac- 

 tice, as ."some of these second hand corks may hold poisonous salts which 

 are soluble in the ordinary flu'ds used as beverages. 



Dr. Kicii said refuse corks were not extensively collected in this country 

 for the purpose of being used again in bottles. 



The Dis Fibre. 



M. Lafon dc Candevalhas made both paper and yarns from the plant called 

 by the Arabs dis. ItgrowsinAlgcriaover an extcntof 2501cagucs. Ityields 



