72 



SCIENCE. 



[Vol. XII. No. 2i 



tions the present line of inquiry was suggested. The question 

 raised was, have all acids that have the same alkali-neutralizing 

 strength the same sourness to the taste? For purposes of testing, 

 a number of ' normal ' solutions were made. Thus, for 



Sulphuric 

 Hydrochlo 



ed 49, 

 36 



The solutions were then of such strength that one cubic centi- 

 metre of each would exactly neutralize one cubic centimetre of a 

 normal solution of carbonate of soda. 



These solutions were then diluted so that in each series one 

 bottle was of one-half the strength of the preceding one. Of course, 

 a point is soon reached where the acid is so dilute that it is impos- 

 sible to recognize its presence by the sense of taste. The bottles 

 •containing these acids, and some bottles containing only water, 

 wei'e placed without regard to order, and the experimenter was re- 

 quested to separate into two groups acid and water by tasting the 

 solutions. Those who had the sense of taste mote thoroughly de- 

 veloped would be expected to taste the more dilute of the acids. 

 No attempt was made to distinguish between the different kinds of 

 acids. The best method has been found to be to test the solutions 

 rapidly, and pick out the samples about which there could be no 

 doubt, and then to go more carefully over the rest a second time. 



In order to obtain the average taste, tests were made by twenty 

 persons, including both sexes and different ages. As the acids are 

 of different apparent strength, the solution of the acids is best seen 

 by a comparison of the most dilute solution tasted in order of 

 strength. This can best be shown by a comparison of the num- 

 bers of bottles tested ; viz., — 



Hydrochlo 



:id, 7-= 



Tartaric acid, 6.5 



These results agree as closely as could be expected, especially 

 •when we consider the unprejudiced position of the experimenter. 

 It will be noticed that the general average of the mineral is a little 

 'higher than that of the organic acids. This may be due to a more 

 persistent and characteristic taste in the former. There seemed to 

 be greater uniformity in the tests for sulphuric acid than for any 

 other, as only four detected any acid in the eighth dilution, and 

 none failed to notice it in the seventh. The amount of acid de- 

 tected, of course, varies with the molecular weights, but the average 

 limit of delicacy is about one part in two thousand parts of water. 



For these tests the solutions were frequently renewed. In one 

 ■case they were allowed to stand for three weeks, when it was found 

 that the three organic acids had lost about all their strength, and 

 at the same time a variety of microscopic organisms had developed 

 at the expense of the acid. These alga^ were different in each 

 acid, though some of the same species were found in all. The ex- 

 amination was kindly made by my friend Mr. V. L. Kellogg. It 

 .may not be in place to give here the details of this examination, but 

 ■only to suggest that a great field of investigation lies open in the 

 direction of these lower orders of life and their relation to the de- 

 struction of chemically pure substances. 



In conclusion, it seems to be true, from what has been stated 

 above, that all acids having the same alkali-neutralizing power are 

 equally sour to the taste, and that the solutions of organic acids 

 rapidly lose their strength. E. H. S. Bailey. 



Lawrence, Kan., July 27. 



Beware of the Deadly Alternating Electric Current. 



At the School of Mines of Columbia College this morning, at 

 eleven o'clock, experiments were undertaken, at the request of 

 Harold P. Brown, electrical engineer, to determine the danger of 

 alternating currents, by Dr. Cyrus Edson and Dr. Charles F. Rob- 

 erts of the New York Board of Health. 



The first dog operated upon was a mongrel dog weighing 6 1 

 pounds, strong, and in good condition. His height was 24 inches ; 

 length from tip of nose to base of tail, 42 inches ; and resistance 

 from the right front leg to the left hind leg, 14,000 ohms. Connec- 

 tion was made by binding a piece of cotton waste saturated with 

 water round the leg with No. 20 bare copper wire. The dog was 



placed in a cage, and the alternating current applied by Dr. Rob- 

 erts at 372.16 volts for five seconds; number of alternations, 288 

 per second. The dog was silent and motionless during the con- 

 tinuance of the current. He gave a few spasmodic gasps thirty- 

 one seconds after current was first applied, and heart ceased beating 

 ninety seconds after current was applied. The dog was immedi- 

 ately dissected by Dr. Roberts and Dr. Peterson, and section of 

 sciatic and pneumogastric nerves, muscular fibres of diaphragm, 

 and lungs, placed under a microscope, and no changes in structure 

 were observed. 



The second dog was a full-blooded Newfoundland, strong, and 

 in good condition, weighing 91 pounds ; length from tip of nose to 

 base of tail, 48 inches ; height, 25 inches ; resistance, 8,000 ohms. 

 Connection was made in the same manner as above. Alternating 

 current applied by Dr. Roberts at 340.5 volts electro-motive force 

 for five seconds. The dog was silent and motionless during con- 

 tinuance of current, howled and gasped for eight seconds after 

 circuit was opened ; but, in the opinion of physicians present, this 

 was pure mechanical action, as the dog was unconscious from the 

 instant the current first reached him. Heart stopped beating in 

 two minutes and fifty seconds after current was first applied. 



The third dog was a half-breed setter and Newfoundland, weigh- 

 ing 53 pounds, 42 inches long from tip of nose to base of tail, and 

 24 inches high ; resistance, 30,000 ohms. Connections were made* 

 in the same way as before. Dr. Roberts applied the alternating 

 current at 220 volts for five seconds. The result was not fatal at 

 four minutes afterwards. Mr. Porter, superintendent of machinery 

 of Columbia College, then suggested, that, as the dog was rigid and 

 motionless during the continuance of the shock, it would be impos- 

 sible for a man in the same conditions to utter a sound or to break 

 the contact in five seconds. Dr. Edson then determined to ad- 

 minister the current at same number of volts for thirty seconds on 

 this account, and on account of the high resistance of this subject. 

 This was done, and during the period of the thirty seconds the 

 voltage rose to 234. The dog died instantly without sound or 

 struggle. The resistance after death was found to be 2,800 ohms. 

 All the physicians present expressed the opinion that a dog had 

 a higher vitality than a man, and that therefore a current which killed 

 a dog would be fatal to a man under the same conditions. It was 

 their opinion that all of these deaths were painless, as the nerves 

 were probably destroyed in less time than that required to transmit 

 the impression to the brain of the subject. 



Dr. Edson invited Prof. Elihu Thomson of Boston, and Dr. Otto 

 A. Moses, to be present with measuring-instruments to check up 

 the voltage, etc.; but neither of these gentlemen put in an appear- 

 ance or responded. 



Dr. Cyrus Edson, Fres. Board of Health. 

 Dr. CH.4RLES F. Roberts, Asst.Prof. Physiol., 



Bellevue Hospital Medical College. 

 Dr. Frederick Peterson. 

 Dr. Frank H. Ingram. 

 Dr. H. A. Haubald. 

 Dr. Schuyler S. Wheeler, Electrician Board 



of Electrical Control. 

 Harold P. Brown, Electrical Engineer. 

 Mr. John Murray Mitchell. 

 Prof. C. E. Colby, Columbia College. 

 Capt. E. L. Zalinski, U.S.A. 

 Prof. L. H. Laudy, Columbia College. 



New York, Aug. 3. 



Note on Breeding-Habits of the Bill-Fish (Tylosurus longirostris). 



On the 25th of June last my attention was called by Mr. Ulric 

 Dahlgren of this city to the fact thafvery young specimens of the 

 bill-fish were to be found in large numbers in the ■ feeder ' of the 

 Delaware and Raritan Canal, north of the town. A few days later 

 I obtained many specimens, and their size at once showed that 

 they had been hatched at the localky where found. In fact, many 

 still showed traces of the yolk-sac. 



So far as I have been able to ascertain, there has been no pre- 

 vious record of the fact that this fish breeds in fresh water, the im- 

 pression with ichthyologists being that they never deposited their 

 eggs beyond salt-water limits. " CHARLES C. Abbott. 



Trenton, N.J., July 31. 



