milligrams less than an actual cubic decimeter of water. The volume, which by common consent is called one cubic centimeter, holds 0.027 milligram less water than that contained in an actual cubic centimeter. For this reason, some are accustomed to speak of milliliters instead of cubic centimeters, but this usage has not been generally adopted. The difference between this volume and the volume of a real cubic centimeter is only about 1 part in 40,000. It is very rarely important to remember that the volume which we call a "cubic centimeter" is arbitrarily referred to the volume occupied by one gram of water, as the liter is arbitrarily referred to the volume occupied by one kilogram of water. The U. S. gallon is, by definition, the volume of exactly 231 cubic inches. This volume of water weighs 58,285.9 grains a t 62'F., in air. It weighs 02.7 grains more in a vacuum. The British "Imperial gallon" is the volume occupied by 70,000 grains, or 10 avoirdupois pounds of water a t 62OF., in air, under a pressure of 30 inches of mercury.
Careful Use of Potent Rickets Remedy Urged. Irradiated ergosterol, the potent new rickets remedy, one ounce of which will do the work of six tons of cod liver oil, is one of the most powerful specific substances which has thus far been isolated. Dr. Alfred Hess of Bellewe Hospital, New York City, recently told the American Pediatric Society that one twenty-five thousandth of a milligram of this parent subztance of vitamin D, an amount almost inconceivably small, is sufficient t o protect a rat from rickets when added to his daily ration. The curative effects of irradiated ergosterol were discovered about a year ago by Lhc combined efforts of Dr. Hess and Prof. A. Windaus of the University of Goettingen in Germany. Znglish investigators working independently also achieved the same results a t about the same time. Dr. Hess has been using thc new remedy in his clinical work and reported today that babies that receive from two to four milligrams a day are almost regularly cured of rickets. "The question arises," declared Dr. Hess, "as to whether this substance may not to a large extent replace cod liver oil in view of the fact that i t can be given in any desired potency and that it has the advantage of being tasteless and odorless. Subsequent clinical tests carried out during the past year have. servedonly to emphasize the practical usefulness of this new remedy. I t is an absolute specific for rickets as well as for tetany, disorders which are so often associated, and it brings about healing of the hones more quickly than any substance which has heretofore been used. The appetite and general condition of the child also show a marked improvement. "A word of warning should be uttered in this connection. Irradiated ergosterol that there is a temptation to use it in exceedingly large doses. I t is being is so ~owet-ful frequently prescribed in doses which are 100, or even 500, times greater than cod Liver oil. Such amounts are quite unnecessary and may even be harmful. A remedy which i q so potent for good may, when given in excess, bring about changes which are as yet Smite unknown and rmsuspected."-Science
