ECONOMY OF LABOUR IN MATHEMATICS 215 



of the notation of Leibnitz for the differential and integral 

 calculus, and moreover its complete discussion of the complex 

 variable, the form — 



(a + bj~^if+ v ^ 



and its differential is shown as clearly as it is in the work of 

 Hartnack. 



How many of our readers are familiar with the work of 

 Brakenridge, Wolfenden, Butterworth, and Holditch ? How 

 many are acquainted with the valuable papers by Weddle, 

 on the construction of logarithms, on the properties of curves, 

 his hundreds of interesting problems about the triangle, and 

 his work on equations ? 



Few indeed have used the extensive tables of dual numbers 

 provided by J. Byrne, and yet these tables, although not 

 perhaps of the value attributed to them by the author, have 

 been found very useful in numerous calculations. 



We began this article by calling attention to the loss sus- 

 tained by science through a neglect of the past history of 

 the subject, and unless we take deliberate steps to counteract 

 this, we are likely to suffer more and more, for with the excep- 

 tion of Sir Thomas Muir, Sir T. L. Heath, and Dr. Gow, we 

 have been in the habit of leaving the history of mathematics 

 to the Germans, who by their splendid collection of works 

 contained in Ostwald's Klassiker der exakten Wissenschaften, 

 the Bibliotheca Mathematica, and the Jahrbuch uber die Fort- 

 schritte der Mathematik, have made it possible for us to dispense 

 with native historians. 



But those who are familiar with German histories will 

 realise how strong national prejudices are, and will have 

 learnt not to expect impartiality. Moreover, there is very 

 great likelihood that we shall have to dispense with German 

 aid for a long period, as the continuance of the Bibliotheca 

 Mathematica and Jahrbuch must be considered very doubtful. 



However painful it may be, we must develop our own 

 resources, and it is well that we should ask ourselves how this 

 can be best effected. 



One of our most pressing needs is a set of works dealing 

 with the history of special branches. Complete histories of 

 the Complex Variable, of the Theory of Groups, of the Solu- 

 tion of Algebraic Equations, of Finite Difference Equations, 



