246 



REPORTS ON THE STATE OF SCIENCE. ETC. 



has stepped in to meet the deficiency. The printing account to February 1928 is 

 given as ' Annexe II bis ' in the Comptes Bendus of the Prague meeting above- 

 mentioned, and may be brought up to date as below : — 



Provision. 



Cost of Printing the Summary. 



Bulletins and Tables. 



The International Seismological Summary is an important part of the work of the 

 Committee, as above remarked. In it are collected the readings sent by nearly 

 250 stations, a Ust of which (together ^vith a number of stations now obsolete, making 

 the total 259) has been printed for circulation to the observatories which receive the 

 Summary. 



During the last six and a half years more than eight years of the Summary have 

 been pubhshed, and the interval between the occurrence of an earthquake and its 

 publication has thus been reduced from about five years to a httle more than three 

 years. Whether further reduction can be made seems doubtful, for some stations are 

 slow in sending in their records, even after several reminders ; and it is of course 

 very desirable to have the details as complete as possible. The following table reviews 

 the progress of the work. The date given in the second column is that of the brief 

 introduction printed with each number of the Summary, and is very closely the date 

 on which the complete MS. for the number was sent to press. The distribution of 

 the number when printed is naturally a few months later. The time taken in pre- 

 paring each number is thus approximately the interval between the first and second 

 columns, and is tabulated in months in the third column. The decrease of this 

 interval was fairly rapid for some years, but has now almost ceased. Meantime the 

 work has increased, owing to the addition of new stations, and to greater vigilance in 

 aU. This increase is indicated roughly by the increase in the number of pages of the 

 Summary (for each three months) shown in the fourth column. In 1918 there Avere 

 altogether 218 pages, dealt with in about 10-2 months, representing a rate of 242 pages 

 in 12 months as shown in the last column. This rate, given for every consecutive 

 set of four numbers, has clearly not fallen off ; the increase in the material has been 

 even faster than that in the time taken to deal with it, so far as these figures can show. 

 They are only a rough guide, hable to be perturbed by exceptional circumstances, 

 such, for instance, as the occurrence of the great Japanese earthquakes of 1923, 

 September 1-2, and following days, which are largely responsible for the figure 110 

 in the fourth column. Many of the pages in this case were descriptive, or in other 

 ways did not call for the heavy numerical work represented in the average page. 



