Correspondence STANDARDIZED NOTATION FOR TITRE DEAREDITOR: The titre method of making computations in quantitative analysis is gradually coming into general use and for that reason there should be adopted an abbreviation for the word, just as the letter N is commonly understood to mean normality. In my reading I have found no similar expression for titre and have therefore found it necessary to create one for use in my classes. The symbol, NaXOa T HCI, is understood in our classes to mean the sodium carbonate titre of an HC1 solution, and of course all other titres can be expressed in a like manner. If possible I should like to publish this letter for two reasons: (1) To ask if a system of abbreviation has been adopted in any considerable number of schools. (2) To suggest that, if no other system is generally employed, this system he adopted. W. P. CORTELYOU
MOTION PICTURES AVAILABLE FOR FREE USE IN EDUCATIONAL INSTITUTIONS DEAREDITOR: Will you please eliminate, for the time being, our film "The Chemical Ethyl Alcohol" from the list of free films in your publication? (See p. 730 of the April issue.) When this film becomes available again we will advise you. You may substitute for the above a film we have, entitled "CottonThe Making of a Turkish Towel." This is a one-reel film which tells the complete story from the picking of cotton to the finished product, and is available in either 16 mm. or 35 mm. width. DE FRENES& CO. WILKES-BARRE, PENNA. 1396
