[MILLER] CHEMICAL LABORATORY RESEARCHES 53 



(5) The Effect of Various Substances on the '^Bunching'' of Yeast 

 By F. I. Eldon 



Many substances when added to wort cause the yeast to grow in 

 clumps or bunches instead of single cells or chains of two or three. 

 Among these are: ammonium chloride, ammonium nitrate, ammon- 

 ium fluoride, ammonia, methyl-green, methyl-ethyl ketone 1%, 

 ethyl ether \%, carbon tetrachloride 0.5%, isoamyl alcohol 1%, 

 normal butyl alcohol 1%, carbon bisulphide 1%. By means of the 

 last two bunches of 50-200 cells may be obtained in from 24 to 48 

 hours. The stock yeast used averaged about 2.5 cells per chain; 

 addition of 1% or 3% acetone reduced this to 1.9 or 1.7 respectively, 

 with more than 5% acetone the bunching was above normal. Phenol 

 behaves like acetone, but the effect is not so marked. 



(Under direction of Professor W. Lash Miller) 



(6) The Effect on the Groivth of Yeast of an Unknown Constituent 



of Malt 



By G. H. W. Lucas ' 



Yeast grows much more readily in malt infusion than in the best 

 of the "artificial" media made up of sugar, salts and water; addition 

 of even one per cent, of the malt infusion to the artificial medium is 

 readily noticeable. It has been found possible to concentrate this 

 unknown constituent by removing the accompanying substances, and 

 it is hoped that it may shortly be isolated. 



(Under direction of Professor W. Lash Miller) 



(7) A Study of the Extent to which Liquids may be Superheated and of 

 the Conditions under which Superheating is Possible 



By C. S. Gilbert, B.S. 



The highest temperatures to which various liquids ha-ve been 

 superheated at atmospheric pressure in open capillary tubes are 

 given below, with the vapour pressures corresponding to these temper- 

 atures, the boiling points and association-coefficients: 



