294 M. F. Kohlrausch on the Absolute Value of the 



y point of fact a rehabilitation of the Leibnitzian measure of force — 

 a rehabilitation, indeed, of a very peculiar character; for the 

 Leibnitzian measure is not supposed to supplant, but to stand 

 pari gradu with its Newtonian rival. 



If the views which I have endeavoured to unfold are correct, it 

 will follow that the received measure of work, of whatever use it 

 may be in simple cases (say when a body moves from rest) as 

 affording within certain limits some rude indications, must be 

 regarded as utterly inadmissible for every scientific purpose. 



6 New Square, Lincoln's Inn, 

 February 26, 1874. 



XXXVI. Determination of the Absolute Value of the Siemens Mer- 

 cury Unit of Electrical Resistance, By F. Kohlrausch*. 



THE more firmly the general adoption of the Siemens Mer- 

 cury Unit is established, the more desirable is it that the 

 ratio which it bears to the scientific standard of resistance, the 

 so-called Absolute or Weber's unit, should be known as accu- 

 rately as possible. A determination of this ratio forms the 

 subject of the present communication. It was carried out in 

 the year 1869 in the Magnetic Observatory at Gottingen, by 

 means of, on the one hand, the splendid instruments for 

 galvanic and terrestrial-magnetic measurements which the Ob- 

 servatory and Physical Institute of Gottingen have acquired 

 through the labours of W. Weber, and, on the other hand, of 

 mercury units which Mr. Siemens kindly had prepared specially 

 for this purpose. 



I may be allowed to premise that I have shunned no 

 labour in order to reach the degree of precision attainable 

 with such means ; and in assuming that this degree of precision 

 has really been reached, I believe I am warranted by years of 

 practice in observations of this nature, no less than by the final 

 agreement of the results. 



The outcome of the investigation is that the Siemens unit is 

 equal, in absolute measure, to 



9717000000 — ', 

 sec. 



or, expressing the same thing by a more convenient number, to 

 n .q, 71 7 earth -quadrant 

 second 



* Translated from PoggendorfFs Annalen, Erganzungsband VI. S. 1, 

 an abstract having been communicated to the Gottingen Academy of 

 Sciences on the 5th November, 1870. 



