Scientific.

Waikato Times, Volume XXVII, Issue 2194, 31 July 1886, Page 2 (Supplement)

Scientific.

A "Scientific" Proposal. — Dr. Cornish, known for his investigations into the nature of cholera, has proposed (according- to Alton's Indian Mail) that as between 300 and 400 persons are judioially sentenced to death in tho Indian Empire and its dependencies, a number of these, say one- tenth, be made, with their own full kuowledge and consent, subjects of expoiimout&as to the spread of cholera, on condition that if they escape their lives be spared. An international commission of experts inig-ht, he suggests, bo appointed to determine upon the experimental test needed to ascertain if cholera is or ia not a disease capable of being communicated from person to person. A New Use for Photography. — A French photoirraphical review, V Amateur JPhotoyrttphi announces that the Brothers of the Christian Schools havo made an ingenious application of photography in teaching deaf mutes to speak. The brothers choose one of their pupils who is able to pronounce perfectly all the letters, diphthongs and syllables, and photograph him at tho very moment of his pronouncing' tho various souuds. All the movements of the mouth necessary for pronounciation have been thus accurately photographed ; and in this manner the deaf mute pupils, though not able to hear words pronounced, are enabled to see them, and study their lesson of pronounciation from the photograph, as we learn it by the ear. Additional Adhesiveness. — It ia said that the adhesive qualities of gum may be very much exalted by the addition of aluminium sulphate (the so-called " patent " alum) to the mucilage. "Two grammes of crystallized aluminium sulphate," says an abstractor in the Chemical Society's Journal, "dissolved in 20 grammes of water, is added to 250 grammes strong gum-arabic solution (2 grammes in 5 grammes of water). Ordiuary solutions of gum-arabic, however concentrated' fail in their adhesive power in many cases, such as the joining together of wood, glass or porcelain ; prepared however, according to the above receipt, the solution meets all requirements. Silver LubTßK«rr-In order to restore the silver lustre to articles from German silver, which they have lost by repeated cleaning, use the following silvering process : Ten parts dry chloride of silver, sixty-five parts cream of tarter, and thirty parts table salt are pulverized and intimately mixed. This powder is then with water stirred to a thin paste, and the article is rubbed with it, left to dry, rinsed off with water, and finally rubbed off with washed chalk." — Exchange. The Electric Light. — It is contemplated to use the electric light in Algiers for night work during the harvest time, in order to escape the heat, which is almost murderous for Europeans and is an obstacle to their carrying on Agricultural work.