VOL.7, NO. 7
T H E BANANA-A
CHALLENGE
1543
Banana Stalks The stalk of the fruit, to which the hands of bananas are attached, contains about 93 per cent water and 1 per cent ash. The ash is very rich in potash, varying from 53 to 63 per cent potassium oxide, depending upon the variety of fruit. During the World War and the period immediately following the conflict, when potash shipments from Germany were curtailed, numerous attempts were made to recover this potash from the stalk^.'^ At the present market price of potash it would require about one ton of the stalks to obtain $3.00 worth of potash. Banana stalks have also been suggested as the basis for a dye13 and as the raw material for the preparation of paper,14.16but the difficulty of collecting the material, in this country a t least, would seem to preclude any great use for it. 1% Ellis, 3. Soc. Chem Ind.,35, 456 (1916). Billings and Christie, Ind. Eng. Chem., 9, 153 (1917). la U. S. Pat. 1,243,042, Oct. 16, 1917. l4 Reifegerste, Wochbld. Papierfabr.. Sondemummer. 57, 75 (1926). "Brit. Pat. 293,219, Aug. 15, 1927.
Boilmg Milk in Aluminum Does Not Destroy Vitamin C. Aluminum cooking utensils have no selective destructive action an the antiscorbutic vitamin of milk, according t o the results of experiments carried out at Mellon Institute of Industrial Research, Pittsburgh, Pa. Milk, man's most negly perfect food, has particular importance in the dietary of the infant and child. There has been a growing tendency to boil milk whenever i t is to be used in supplemental feedings, or whenever a supply is of doubtful origin. I n thus safeguarding the health of children against microtjrganisms and in providing for better assimilation of the proteins, mothers may be assured that when they use aluminum utensils for the preparation of milk they are not depriving this invaluable foodstuff of its antiscorbutic properties. I n the Mellon Institute experiments milk was boiled Lightly for five minutes in aluminum or glass containers. Some destruction of vitamin C occurred in each case as- a -result of the boilinn. meater action than did -. but the metallic utensils exerted no . those of glass. Another interesting observation is that winter milk from ensilage-fed cows is practically as potent in vitamin C as the best summer milk from cows on pasturage. Full details of the experiments will be supplied by Mellon Institute on request.
Glass Resists IS-Ton Pressure. A bit of glass about a sixteenth of a square inch in area, bearing a load of approximately fifteen tons, is the simple new weapon of science developed by Prof. Thomas C. Poulter of Iowa Wesleyan University. It served as a tiny window looking into a pressure-chamber, where experiments are performed under the tremendous pressure of thirty thousand atmospheres. The little glass window is ground perfectly flat and set against a disk of high-speed steel, also ground perfectly flat. There is no gasket; the pressure attends to the sealing of glass against metal.-Science Service
