stedet. Herom kan jeg henvise til den foranstaaende Af- 

 handltng af Professor .Mulm. Kronometrenes Gang be- 

 stemtes efter Sammenligning med det ombord værende Nor- 

 malkronometer, hvis Stand og Gang var bestemt væsentlig 

 efter telegrafiske Tidssignaler fra Christiania Observatorium 1 . 

 Paa et Par Steder toges Kronometrets Stand efter dets 

 Stand for Greenwich Tid og Længden af Observations- 

 stedet efter Kystkartet. 



Observationerne af alle Elementer gjordes i Teltet, 

 Ved Observation af Solen aabnedes Teltet neton saavidt i 

 Kum og Tid. som var nødvendiet. 



b. Horizontal Intensitet. 



Observationerne og Beregningerne udførtes elter In- 

 struktionerne i "A Manual of Scientific Enquiry": Fourth 

 Edition. 1871 Side 96 til 101. Unifilar-Magnetometrets 

 Konstanter var ved Kew-Observatoriet bestemte saaledes: 



ved 62° F. 



. Correction for Delingsfejl ved Afbøjningsstangen 



ved 1 Foot. == + 0.00002 Foot. / 

 .. 1.5 - = + 0.00004 ( 



Svinge-Magnet, Værdi af 1 Skaladel = 1.'9. 



Afbøjningsmagnetens Correction til 35" F = 

 0.000130 (t„ -- 35) -f 0.00000056 (t„ -- 35;-. 



Induktionskoefficient a = 0.000195. ' 



Log ;i- K ved 60° F = 1.69708. 



Der er desuden givet forskjellige Hjælpetabeller. blandt 

 hvilke en for Værdierne af Log. .t- K og Log ' - : r 3 for 

 forskjellige Temperaturer : 



of observation. For details on this head. I can refer to 

 the foregoing Menioir. by Professor Mohn. The rate of 

 the chronometer was determined by comparison with the 

 standard chronometer on board. the error and rate ol 

 which were found chiefly by means of the time-signals 

 telegraphed from the Christiania Observatory 1 . At one 

 or two points. the error of the chronometer was tåken 

 trom its error on Greenwich time and the longitude of the 

 place of observation on the coastal chart. 



The observations of all the elements were made in the 

 tent. For observations of the sun. the tent was opened 

 to just the necessary extent in space and time. 



b. Horizontal Intensity. 



The observations and computations were made in 

 accordance with the instructions contained in "A Manual 

 of Scientific Enquiry:" Fourth Edition. 1871. pp. .96 — 101. 

 The constants of the Unifilar Magnetometer bad been de- 

 termined at the Kew Observatory. as follows: - 



Correction for errors of division of Deflecting Rod 

 at 1 Foot = + 0.00002 foot 

 .. 1.5 — = + 0.(1(11)04 .. 



Yibration Magnet, value of 1 division of Scale zz 1.'9. 



Deflecting Magnet, correction to 35" F. = 

 0.000130 (t„ -- 35) + 0.00000056 (t — 35) 2 . 



Coefhcient of Inductiou u = 0.000195. 



at 62° F. 



Los ;c 2 K at C>0° F 



1.69708. 



Moreover, di vers auxilinry Tables are annexed. one 

 of which gives the valnes of Log. r 2 K and of Log. ' ■_. i" 

 at different temperatures. 



Temp. 

 F 



1.0 





Sum Exempel paa Observationernes Udforelse og Be- 

 regning hidsættes følgende, efter de fra Kew erholdte trykte 

 Blanketter udfyldte, Skemata. 



1 Se den citerede Afh. Siile 2. 



To show the mode of taking and computing the ob- 

 servations. copies of the printed forms in use at Kew Ob- 

 servatory have been filled out. and here subjoined. 



S.i- Professor Molm's Memoir. 



