Febkuauy 24, 10i.'i 



SCIENCE 



207 



was the General Society of Mechanics and 

 Tradesmen, to which the testator left 

 $1,800,000. 



The will of Cora M. Perkins gives her re- 

 siduary estate to Columbia University, in 

 addition to a direct bequest of $30,000 for 

 chemical research. 



A Rei'tee dispatch from Brussels states that 

 Louvain University has received a legacy of 

 $100,000 toward erecting a special building for 

 cancer research. 



Dr. M. C. Merrill, professor of horticulture 

 at the Utah Agricultural College, has been ap- 

 pointed professor of horticulture and dean of 

 the new College of Applied Arts at the Brig- 

 ham Young University, Provo, Utah. 



T. L. Patterson, Ph.D., formerly of the 

 physiological department of the State Univer- 

 sity of Iowa College of Medicine, has been 

 appointed professor and director of the depait- 

 ment of physiology at the Detroit College of 

 J\Iedieine and Surgei'v. 



Dr. Alice Sullivan has sufficiently recov- 

 ered from her accident of last summer in the 

 Colorado floods to assume her position as 

 instructor in psychology at the University of 

 Illinois. 



DISCUSSION AND CORRESPOND- 

 ENCE 

 KILOBAR, KILOCAL, KILOGRAD 



Ik a letter just received from The Meteoro- 

 logical Office, Professor Whipple very kindly 

 informs me of the result of a question put to 

 the Secretary of the Chemical Society regard- 

 ing the attitude of British chemists regarding 

 the bar. 



While the opinion expressed is to be regarded 

 as unofficial, Professor Philip says: 



"Your letter in reference to the definition of 

 the 'bar' was considered by our Publication 

 Committee. The general opinion is that very 

 few English chemists use the 'bar' as a unit of 

 pressure on either basis. There was a feeling, 

 however, that in view of the use of the 'bar' 

 in Langmuii''s papers and other communica- 

 tions emanating from the same quarter (see 



e. g. Dushman in the General Electric Beview, 

 1920-1) English chemists would be more likely 

 to use the 'bar' in that sense than in the sense 

 employed by meteorologists." 



It will be recalled that meteorologists in 1913, 

 quite unaware of the fact that the bar had been 

 accurately defined by Professor T. W. Richards 

 in 1903, and thinking they were coining a 

 new word, adopted the bar as the unit of pres- 

 sure but gave it the value of a megabar. My 

 friendly correspondent, a meteorologist of 

 prominence, adds: "This looks as if the con- 

 fusion is likely to spread. We shall have a 

 permanent ambiguity like those in the words 

 billion and calorie." 



To this, I have answered : There need be no 

 confusion if meteorologists will simply write 

 kilobar, where they now use millibar. 



The practical unit of pressure is 1000 bars, 

 the bar being the pressure expressed in terms 

 of force which will give an acceleration of 1 

 centimeter per second per second to one gram 

 of matter. 



It is the natural basic unit, strictly C. G. S. 

 and was in legitimate use by chemists and 

 physicists 10 years previous to its appropria- 

 tion by meteorologists. 



With regard to the calorie, it will no longer 

 be necessary to specify the calorie as the gram 

 calorie or therm. The word calorie by itself 

 will mean the amount of heat that will raise 

 the temperature of a gram of pure water from 

 1000 to 1003.66 Kelvin-kilograds. The larger 

 unit, much used by engineers, being the amount 

 of heat required to raise the temperature of 

 one kilogram of water, can be called the hilo- 

 cal. 



The scale of temperature which has been 

 used without difficulty at Blue Hill Observatory 

 for the last five years, makes the thermal co- 

 efficient of the expansion of a gas (air) at con- 

 stant pressure .001 instead of .00366. 



This is very easily accomplished by making 

 zero on the scale, the absolute zero ( — 273.12° 

 Ac) and making the freezing point of pure 

 water at megabar pressure, 1000. There are 

 numerous advantages in the use of the scale. 

 When used in connection with kilobar pres- 

 sure, values of temperature and pressure are 



