( 244 ) 
These results are expressed in millimeters of the scale and they 
represent the total amplitude on that scale diminished by 320 Mm. 
The 2ed and the 4% column contain the results obtained for the 
spring and the autumn; the 3rd contains the means of two consecutive 
results for the spring; the 5 the differences autumn — spring 
obtained by substracting the numbers of the 3"4 column from those 
in the 4%, The differences prove to be very small; their mean 
amounts only to — 0,38 Mm. or, if we exclude 1878 on account of 
a possible displacement of the lens, — 0.58 Mm., 7.e. —0’2 or 
—0./3 respectively, whereas the effect of 1° R. is 0.’6 in the beginning 
and about 1’ afterwards. Besides, the sign of the mean difference is 
the reverse of what we should have found, when the amplitude of 
the pendulum lags behind the temperature. Thus already this superficial 
investigation seems to show, that there is no term in the amplitude 
analogous to the supplementary term in the rates. 
VI. Comparison of the results. 
24. If we consider the results obtained in the preceding pages in their 
mutual relation, we are struck in the first place by the fact that the 
clock Honwt 17, which at present has been going for more than, 
forty years, far from showing the defects of old age, has increased on 
the contrary in regularity of rate in the course of the years. We 
have seen that both in the period 1862—1874 and in that of 1878— 
1898 the greatest regularity was only reached after some years. It 
may be pointed out now that this regularity has also increased from 
period to period. 
For we found for the mean deviation of the monthly means from 
a simple curve (1st and 2"d period) or from a constant value (3"4 
period) the numbers: 
1862—1874 + 0:.0291 
1879—1896 "0237 
1899— 1902 ‚0215 
The diminution of the mean deviation is considerable and where- 
as in the 34 period the amelioration in the clock’s position may have 
contributed towards this diminution, the difference between the first and 
the second is very striking. We have to consider in this connection 
that, for the two former periods, a whole year at the beginning has 
been left out of consideration, whereas for the third the 5t® month 
has already been taken into account. 
The only point in which the second period is at a disadvantage 
