ox SEISMOLOGICAL INVESTIGATIOX. 



257 



XI. Tables of Certain Small Fractions of an Hour. 



The film used with the Milne Horizontal Pendulum is supposed to be 

 driven at the rate of 60 mm. per liour. In consequence of changes in 

 temperature, varying resistances in the unrolling of the film, and for other 

 reasons, measurement between the time marks will sometimes slightly 

 vary. The result of this is that the observer when determining the exact 

 commencement of a disturbance finds he has to work out certain fractions 

 of an hour. For example, he may i-equire to know the value of j?-^ of an 

 hour, or T^trV" ^^ ^"^ hour, which ai-e respectively 31 mins. 31 '5 sees., and 

 31 mins. 07 "7 sec. 



Such results are shown in the following table drawn up by my assistant, 

 Shinobu Hirota. 



Inasmuch as measurements less than O'l mm. cannot be made on the 

 time scale, it is evident that for all ordinary computations the decimals in 

 the following table are not required (see British Association Report, 

 189G, p. 183). 



Distance 

 from 



Time Mark 

 to soaie 



Piiase of a 

 Disturb- 

 ance 



MM. 



0-25 



0-50 



0-75 



1 



2 



S 



4 



6 



6 



7 



K 





 10 

 It 

 12 

 K! 

 14 

 15 

 Ifi 

 17 

 18 



la 



20 

 21 

 22 

 2» 

 24 

 25 

 26 

 27 

 28 

 21) 

 SO 

 SI 



:v> 

 :« 



S4 

 X5 



s«; 



S7 

 S.S 

 39 

 41) 

 41 

 42 

 4:t 

 44 



Intervals betwekn* Time Marks ox a Film 



MM. 



6H-U 



l.er 



1 lioiir 



MM. 



5S-25 



per 



1 hour 



M. 





 

 



1 



o 

 3 

 4 

 5 

 6 

 7 

 8 

 9 

 10 

 II 

 12 

 13 

 U 

 15 

 15 

 17 

 18 

 10 

 20 

 21 

 22 

 23 

 24 

 25 

 2G 

 27 

 28 

 30 

 31 

 32 

 33 

 34 

 35 

 3G 

 37 

 38 

 33 

 40 

 41 

 42 

 43 

 44 

 45 



189S. 



15-51 

 31-(I3 

 4G-55 

 02-07 

 Oi-14 

 OG-20 

 OS-27 

 10-34 

 12-41 

 14-48 

 lG-55 

 18-G2 

 20-G9 

 22-76 

 24-83 

 2G-90 

 28-96 

 31-03 

 33-10 

 35-17 

 37-24 

 39-31 

 41-38 

 43-45 

 45-51 

 47-58 

 49-G5 

 51-72 

 53-79 

 55-86 

 57-93 

 00-00 

 02 -U7 

 04-14 

 06-20 

 (18-27 

 10-34 

 12-41 

 14-48 

 16-55 

 18-62 

 20-G9 

 22-76 

 24-83 

 2G-90 

 28-97 

 31-03 



15-45 

 30-90 



46-35 



1 01-80 



2 03-60 



3 05-41 



4 07-21 



5 09-01 

 G 10-81 



7 12 61 



8 14-42 



9 16-22 



10 18-02 



11 19-82 



12 21-63 



13 23-43 



14 25-23 



15 27-03 



16 28-84 



17 30-64 



18 32-44 



19 ,34-25 



20 36-05 



21 37-85 



22 39-65 



23 41-46 



24 43-26 



25 45-06 



26 46-86 



27 48-67 



28 50-47 



29 52-27 



30 54-07 



31 55-88 



32 57-68 



33 59-48 



35 01-28 



36 03-09 



37 04 89 



38 06-69 



39 08-49 



40 10-30 



41 12-10 



42 13-90 



43 15-71 



44 17-51 



45 19-31 



MM. 



53-50 



per 



1 hour 



M. s. 

 15-38 

 30-77 



46-15 



1 01-53 



2 03-07 



3 04-61 



4 06-15 



5 07-69 



6 09-23 



7 10-77 



8 1-2-31 



9 13-84 



10 15-38 



11 16-92 



12 18-46 



13 20-00 



14 21-53 



15 23-07 



16 24-61 



17 26-15 



18 27-69 



19 29-23 



20 30-77 



21 32-31 



22 33-84 



23 35-38 



24 36-92 



25 38-46 



26 40-00 



27 41-53 



28 43-07 



29 44-61 



30 46-15 



31 47-69 



32 49-23 



33 50-77 



34 52-31 



35 53-84 



36 55-38 



37 56-92 



38 58-46 



40 00-00 



41 01-53 



42 03-07 



43 04-61 



44 06-15 



45 07-G7 



MM. 



58-75 



Iier 



1 hour 



M. .s. 

 15-31 

 30-63 



45-95 



1 01-27 



2 02-55 



3 03-83 



4 05-10 

 6 06-38 



6 07-66 



7 08-93 



8 10-21 



9 11-49 

 10 12-76 

 U 14-04 



12 15-31 



13 16-59 



14 17-87 



15 19-16 



16 20-42 



17 21-70 



18 22-97 



19 24-25 



20 25-53 



21 26-80 



22 28-03 



23 29-36 



24 30-63 



25 31-91 



26 33-19 



27 34-46 

 23 35-74 



29 37-02 



30 38-29 



31 39-57 



32 40-85 



33 42-12 



34 43-40 



35 44-68 



36 45-95 



37 47-23 



38 48-51 



39 49-78 



40 51-06 



41 52-34 



42 53-61 



43 51-89 



44 6G-17 



MM. 



69-0 



pnr 



1 hour 



II. .'^. 

 15-23 

 30-50 



45-75 



1 01-01 

 02-03 

 03-05 

 04-06 

 05-08 

 06-10 

 07-11 



8 08-13 



9 09-15 



10 10-16 



11 11-18 



12 12-20 



13 13-22 



14 14-23 



15 15-25 



16 16-27 



17 17-28 



18 18-30 



19 19-32 



20 20-33 



21 21-35 



22 22-37 



23 23-39 



24 24-40 



25 25-42 



26 26-44 



27 27-45 



28 28-47 



29 29-49 



30 30-50 



31 31-52 



32 32-54 



33 33-55 



34 34-57 



35 35-59 



36 36-60 



37 37-62 



38 38-64 



39 39-66 



40 40-67 



41 41-69 



42 42-71 



43 43-72 

 41 44-74 



MM. 



59-75 



per 



1 hour 



M. .s. 

 15-06 

 3U-12 



45-18 



1 00-25 



2 00-50 



3 00-75 



4 01-00 

 6 01-25 



6 01-50 



7 01-75 



8 02-01 



9 02-26 



10 02-51 



11 02-76 



12 03-01 



13 03-26 



14 03-51 



15 03-76 



16 04-01 



17 04-26 



18 04-51 



19 04-77 



20 05-02 



21 05-27 



22 05-52 



23 05-77 

 2t 06-02 



25 06-27 



26 06-52 



27 01-77 



28 07-03 



29 07-23 



30 07-53 



31 07-73 



32 08-03 



33 08-28 



34 08-53 



35 08-78 



36 09-03 



37 09-29 



38 09-54 



39 09-79 



40 10-04 



41 10-29 



42 10-54 



43 10-79 



44 11-04 



