98 ANNUAL OF SCIENTIFIC DISCOVERY. 



GLASS SHADES. 



THE largest glass shade ever produced was lately blown at Birming- 

 ham by an English workman. It is 62 inches by 26^ inches in diam- 

 eter, and contains nearly 40 pounds of glass. A secret in blowing 

 great glass bubbles was lately described in the London Builder. It 

 consists in simply moistening the mouth with a little water before 

 blowing. The water is converted, in the interior of the drop, into 

 steam, which greatly aids the breath in extending the dimensions of 

 the "bell." 



EXPANDING MODEL OF A MAN. 



A MECHANICAL curiosity, called the " Expanding Model of a Man," 

 was contributed to the Great Exhibition, by Count Daru, an exiled 

 Pole. The figure represents a man five feet high, in the proportions of 

 the Apollo Belvedere. From that size the figure can be proportionally 

 increased to six feet eight inches ; and, as it is intended to measure 

 the clothing of an army, it is so constructed as to be capable of adjust- 

 ment in every part to the particular proportions of each individual. 

 This is obtained by mechanism composed of 875 framing pieces, 48 

 grooved steel plates, 163 wheels, 202 slides, 476 metal washers, 482 

 spiral springs, 704 sliding plates, 497 nuts, 8500 fixing and adjusting 

 screws, with numerous steadying pins ; so that the number of pieces is 

 upwards of 7000. 



IMPEOVED SAFETY LAMP. 



THE great objection against the use of Davy's safety lamp was 

 the insufficient light it afforded to the miners. This has been rem- 

 edied by M. Eloin, of Belgium, who has constructed a lamp perfectly 

 safe, and giving a light equal to six Davy lamps. It consists of a lamp 

 surrounded by a strong short glass cylinder, surmounted by an iron or, 

 brass one, capped with coarse wire gauze ; the air for supporting com- 

 bustion being admitted through fine wire gauze at the bottom, and 

 made to impinge directly upon the flame. This air being only such as 

 is necessary to support the flame, and the combustion being perfect, 

 the portion of the cylinder above the flame must always be filled with 

 the products of combustion, and never with an explosive atmosphere. 

 The weight of the lamp is by no means objectionable ; it is inexpen- 

 sive, and the power of perceiving the presence of fire-damp is fully 

 equal to the original Davy. London Mining Journal. 



