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be strapped in the dogs' collars and read at corresponding times. Soon after beginning to administer alcohol it was often noted that the normal dogs were playing actively while the others were quiet. A quantitative expression of this difference is given for the months indicated in 1896, in Fig. 9, and since a number of investigations have shown that muscular and mental ability in men and animals tend to vary with the barometer, its curve for the time is superimposed.1 Bum is seen to develop only 71% of Nig's, and Tipsy only 57% of Topsy's spontaneous activity. A like tendency to quiet was noted in the other dogs to which alcoholic liquors were given with exception of those having beer. They, to all appearance, remained as lively as ever.2

These results give, of course, no expression of the quality of activity, and to devise a test that would give the comparative ability of the dogs as to strength, endurance, and resistance to fatigue, they were all taught to retrieve a ball when thrown. When it was desired to make a test, the dogs were all taken to the university gymnasium, and a rubber ball was thrown across the room, a distance of one hundred feet, as fast as it could be retrieved. A record was kept of all the dogs that started for the ball, and of the one that brought it back. One hundred balls constituted a test, and to throw them consumed about fifty minutes.

The first series consisted of 1400 balls, thrown on fourteen successive days, January, 1896, and the two normal dogs retrieved 922, the alcoholics, 478. This gives the alcoholics an efficiency of 51.9% as compared with the normals. Bum's ability

that would permit the release of one tooth of the escapement every time the watch was shaken. A very delicate pedometer resulted that recorded every movement of the animal. Two of these were carefully adjusted so as to run alike, in whatever position placed or however shaken, and were then placed in stout leather pockets in the collars of the two dogs whose activity it was desired to test. They were then read daily at exactly the same time, six o'clock P. M. To insure any change in the watches affecting the results, they were interchanged from dog to dog every three days, so that each dog wore the same watch the same number of days. No such variation, however, in the watches was observed to occur.

1 For the barometric record we are indebted to Mr. Martin Green, of Worcester.

2 Dr. Stewart obtained a similar result with rats, except that there was an initial increase of activity on beginning administration of alcohol.

as compared with Nig's is only 32% (see Fig. 10). Tipsy and

Balls 100

60

40 Rests

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Days 7

Ability

Fatigue

44%

FIG. 11. Chart of Ball Tests.

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Bum also gave evidence of very much greater fatigue. A similar series of 1000 balls, November, 1896, in which Bum and Nig only participated, shows about the same result, and expresses (Fig. 11) these relations as to fatigue more exactly. Nig's curve of achievement is also seen to run much closer to his curve of attempt than in Bum's case, in both charts, and this affords good evidence of his greater alertness, strength, and energy.

These differences, especially on the psychic side, are well shown by all the photographs that have been taken. Comparison of the faces in Figs. 5, 12, 13, and 20 demonstrate this too clearly to require further comment. It should be noted, however, in Fig. 20, that Bum is completely blind, which give the eyes a somewhat more wideawake expression, and the direct sunlight, in which the picture is taken is rather strong for the eyes of the other dogs.

Administration of alcohol was discontinued November 1, 1898, in order to ascertain whether the effects of alcohol already noted were transient or permanent. This point in the research has special reference to its influence on progeny, as will be described under that head, but it is also of interest in connection with the normal activity of the animals. This was at the beginning of Tipsy's last gestation period, and no marked change in her general behavior could be noted up to the time of her death the following December.

Bum's activity improved slowly, so that by the end of a year it had attained practical equality with Nig's, a test with the watches at this time giving the relation of 95% to Nig's 100%. Ball tests, also, made in the spring and fall of 1899, showed him to be about Nig's equal both in alertness and endurance.

During the winter of 1899-1900, without any apparent cause, atrophy of both retinæ began to be noticeable, and by the spring

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