PEEFACE 



T AM very conscious of the delay which has intervened between the announce- 

 ment of the publication of these Tables and their appearance. This delay has 

 been chiefly due to two causes. First the great labour necessary, which largely 

 fell on those otherwise occupied, and secondly the great expense involved (a) in 

 the calculation of the Tables, and (6) in their publication. This matter of expense 

 is one which my somewhat urgent correspondents, I venture to think, have entirely 

 overlooked. It is perfectly true that only one single Table in this volume has 

 been directly paid for, but a very large part of the labour of calculation has been 

 done by the Staff of the Biometric Laboratory, whose very existence depends on 

 the generous grant made to that laboratory by the Worshipful Company of 

 Drapers. Our staff is not a large one and it has many duties, so that the progress 

 of calculation has of necessity been slow. Even now I am omitting projected 

 Tables, which I can only hope may be incorporated in a later edition of this 

 work, e.g. Tables of the Incomplete B- and F-functions, and the Table needed to 

 complete Everitt's work on High Values of Tetrachoric r when r lies between 

 '80 and TOO. It would only satisfy my ideal of what these Tables should be, 

 had I been able to throw into one volume with the present special tables, 

 extensive tables of squares, of square roots, of reciprocals and of the natural 

 trigonometric functions tabled to decimals of a degree. Logarithmic tables are 

 relatively little used by the statistician to-day, which is the age of mechanical 

 calculators, and he is perfectly ready to throw aside the fiction that there is any 

 gain in the cumbersome notation of minutes and seconds of angle a system 

 which would have disappeared long ago, but for the appalling 'scrapping' of 

 astronomical apparatus it would involve. But the ideal of one handy book for 

 the statistician cannot be realised until we have a body of scientific statisticians 

 far more numerous than at present. Statisticians must for the time being carry 

 about with them not only this volume but a copy of Barlow's Tables, and a 

 set of Tables of the Trigonometrical Functions. 



