572 TRANSACTIONS OF THE AMERICAN INSTITUTE. 



ducing a singular efiect, reminding one of the lamps which the 

 Hindoo maidens cast upon the waters of the Ganges as mystic 

 messengers to their distant lovers, or to their spirits after death. 



Razors. 

 Engineers, as a class, were the first to head the modern " beard 

 movement" in this country; but many may like to read the fol- 

 loAving extract from a little work by Mr. Kingsbury, a practical 

 razor-maker, of Bond street: "The edge of a razor, a pen-knife, 

 and every other very keen instrument, consists of a great number 

 of minute points, commonly called teeth, which if the instrument 

 is in itself good condition, follow each other through its whole 

 extent with great order and closeness, and constitute, by their 

 unbroken regularity, its excessive keenness. The edge of such an 

 instrument acts on the beard, the skin or anything else, not so 

 much by the direct application of weight or force as being drawn, 

 even slightly along it; because by this operation, the fine teeth of 

 w^hich it consists pass in quick succession, in the same direction, 

 and over the same part of the substance. My readers wil be con- 

 vinced of this if they will make the following experiment on their 

 glove or their hand, as they like best : Let them hold the razor 

 either perpendicular or obliquely, and press on it with some con- 

 siderable force in a direct line from right to left, and they will 

 have no great reason to fear the consequences. But let them 

 move it from that direction, let them draw it towards them, or 

 push it from them, in the smallest degree, in the gentlest manner, 

 and it will instantly make an incision. When they have made this 

 experiment, they will be convinced of the truth of what I have 

 asserted, namely, that in the operetion of shaving, very little 

 weight and even very little force are necessary." Hence it fol- 

 lows that the best razor will have the teeth of its edge set almost as 

 regularly as a good saw, and that the best test in buying a razor 

 is to examine the edge by means of a strong magnifying glass. 

 This also explains the good effect on the keenness of a razor 

 caused by dipping it in hot water, which necessarily clears the 

 edges of any small clogging substances. — London Engineer. 



" Slag " as a Substitute for Emery. 

 Among the most useful applications of-, waste substances to the 

 advancement of industrial art, we think may prove an invention 

 recently patented in England. It is the utilization of the immense 



