24 KANSAS ACADEMY OF SCIENCE. 



This relative bitterness is best illustrated by the diagram: 



— ~^ 



strychnine- 



AVERAGE OF FORTY OBSERVATIONS. 



A comparison of authorities will show that there is a wide difference of opinion 

 as to the amount of some of those substances that can be detected by the sense of 

 taste. Some state that one part of strychnine in 30,000 parts of water can be de- 

 tected, while others place the figures at one part in 700,000. The above experiments 

 show that the latter is nearer the truth. 



Twelve of the experimenters were able to detect one part of strychnine in 1,280,- 

 000 parts of water; or if one cubic centimeter be considered as sufficient for a taste,, 

 they were able to detect x7?yVoo ^f a grain. Several who had taken large quantities 

 of quinine were able to detect relatively small quantities of this substance. 



The fact that has been previously noticed by chemists, that solutions of aloin 

 lose their strength on standing, was confirmed. The curious anomaly was apparent, 

 that while some could taste solutions of aloin as dilute as those of strychnine, others 

 could not detect any bitterness in a solution which contained one part of aloin in 

 1,250 parts of water. We were able to detect chemically, by concentration, the 

 strychnine in -^^ of a cubic centimeter of a solution that contained less than one 

 part in one million parts of water. So it would seem that a chemical test is about 

 equal to the average delicacy of the sense of taste for this substance. In the case of 

 any particular individual, however, the chemical test is liable to be more delicate. 

 It is not necessary to say that the latter is more reliable, for it not only detects a bit- 

 ter substance, but tells what particular principle is present. We have found that 

 sulphuric acid and potassic bichromate gave the most delicate results. It is our 

 intention to continue these experiments, and, by having tests made by a much larger 

 number of persons, to more thoroughly substantiate our results. 



ON THE SWEETNESS OF INVERT SUGAR, WITH SOME NOTES ON ITS 



PREPARATION. 



BY .1. T. WILLARD, MANHATTAN, KAS. 



A solution of cane sugar possesses the power of rotating a ray of polarized light 

 to the right. If this solution be treated for a few minutes with a dilute mineral acid, 

 it is changed so that it becomes levorotary. Hence it is said to be inverted, and 

 the product is called invert sugar. It is produced, though not so rapidly, by the ac- 

 tion of organic acids on cane sugar. When fruit is cooked with sugar, much of the 

 sugar is inverted. A determination of the relative sweetness of the two sugars thus 

 assumes a practical aspect. 



Invert sugar is usually said to be a mixture of equal equivalents of dextrose and 



