[ 707 ] 
Photographic Notes. 
The Metric System.—The following is a list of weight equiva- 
lents and measure equivalents :— 
WEIGHT EQUIVALENTS. 
To convert grains into grammes, multiply by 0°065. 
To convert grammes into grains, multiply by 15°5. 
To convert drachms into grammes, multiply by 3°9. 
To convert ounces avoirdupois into grammes, multiply by 28:4. 
To convert pounds avoirdupois into grammes, multiply by 
4536. 
MEASURE EQUIVALENTS. 
To convert cubic centimetres into grains, multiply by 15'5. 
To convert cubic centimetres into drachms, multiply by 0°26. 
To convert cubic centimetres in ounces avoirdupois. multiply 
by 0°036. 
To convert pints into cubic centimetres, multiply by 473. 
To convert litres into ounces avoirdupois, multiply by 35°3. 
To convert gallons into litres, multiply by 3°8. 
Lamp and Reflector for the Flash-Light.—The Lamp and 
Reflector for using the Flash Light shown in the annexed engrav- 
ings were invented by Mr. Redwood. Through the kindness of 
Messrs. Marion and Co., of Soho Square, London, we are 
ITC. te 
enabled to show to our photographic friends engravings of Mr. 
Redwood’s Patent Lamp and Reflector for using the Flash-Light in 
taking portraits. The Lamp (Fig. 1) has two circular wicks (which 
only need be saturated with the spirit before lighting), inclining 
towards each other, through which, by means of the pneumatic 
