IQ KANSAS ACADEMY OF SCIEXCE. 



so intinately associated ones. We express this in common conversation, 

 when we associate the Irishman with his peat fire smoke, the Italian 

 with his macaroni and cheese, and the German with his onions and sour 

 beer. These appeal to our sense of smell and recall the nationality in- 

 stantly. 



The nerves of taste, too, can pick out substances of different quality so 

 delicate that neither chemical nor physical science is acute enough to follow 

 them. From some experiments made in the laboratory of the State Uni- 

 versity, it has been shown that a normally-endowed person can pick out one 

 part of a bitter substance in about 700,000 parts of water; but one part of 

 sugar in 12S parts of water is the limit of sensibility. There are those, how- 

 ever, who, either from superior training or from natural delicacy of the 

 sense, can detect one part of a bitter substance even if it is dissolved in a 

 million and a quarter parts of .water. They can detect one 170,000th part of a 

 grain o' strychnin, for instance. That is beyond the delicacy of the chemical 

 test for thiF poison, but not very much beyond it. And it must be remem- 

 bered that the chemical test says that the substance is strychnin, while the 

 taste only teUz us that the substance is bitter. It may be any bitter prin- 

 ciple, as aloin. morphin, or quinin. 



In the field of Toxicology, also, as we have a knowledge of poisons, minute 

 quantities of which are fatal, we have also extremely delicate methods for 

 the detection of these poisons. One is reminded in this science of the 

 progiess that is made in building huge projectiles and in heavier armor to 

 withstand the force of the projectiles. With the Krupp gun comes the 10-inch 

 chilled stet-l for it to penetrate. With the increase in projectile power comes 

 the greater ability to withstand these projectiles. We cannot tell why that 

 oaolecule C21 H22 N2 O2, which we call strychnin, has such deadly power, but 

 we can find it even if it is present in very minute quantities in the body. 

 From a mass of organic matter many thousand times the amount, it is pos- 

 sible to separate, after repeated purifications, the pure needle-shaped crystals 

 of strychnin, that may be identified by a dozen distinct and characteristic 

 tests. We con go out of the line of chemical investigation and make physio- 

 logical tests that will verify our results from another standpoint. I have 

 experimented with a frog, for instance, by injecting less than one 125th of a 

 grain beneath the skin, and seen the peculiar spasms so characteristic of this 

 poison appear in less than a minute, and in three minutes the frog was dead. 

 This was with strychnin that had been taken from the body of a man who 

 had been poisoned by a fatal dose. 



There is also another deadly drug, aconite, so poisonous that a still 

 smaller portion than that noticed for strychnin is liable to prove a fatal dose. 

 Here, too, the physiological test can be relied upon with certainty. It is 

 stated that if one 1,000th of a grain of this alkaloid be dissolved in 

 water and placed upon the tongue it will cause a distinct numbness that will 

 last for an hour, while one 100th of a grain dissolved in alcohol and rubbed 

 on the skin will produce loss of feeling that will last for some time. Ex- 

 perimentB have shown that one 50th of a grain given to a bird will kill it 

 almost instantly. 



I need not speak of that interesting active substance, atropin, which the 

 oculist will inject into your eye when he examines it. We know that as small 

 a quantity as one 3,000th of a grain will dilate the pupil. Here then we 

 have a delicate and efficient test for this drug. 



In the field of organic chemistry the advances that have been made are 



