MATHEMATICS. 



MATHEMATICS. 



Airy. Works by G. B. AIRY, Astronomer Royal : 



ELEMENTARY TREATISE ON PARTIAL DIFFERENTIAL 

 EQUATIONS. Designed for the Use of Students in the Univer- 

 sities. With Diagrams. Crown 8vo. cloth. $s. 6d. 

 It is hoped that the methods of solution here explained, and the instances 



exhibited, will be found sufficient for application to nearly all the important 



problems of Physical Science, which require for their complete investigation 



the aid of Partial Differential Equations. 



ON THE ALGEBRAICAL AND NUMERICAL THEORY OF 

 ERRORS OF OBSERVATIONS AND THE COMBINA- 

 TION OF OBSERVATIONS. Crown 8vo. cloth. 6s. 6d. 

 In order to spare astronomers and observers in natural philosophy the 

 confusion and loss of time which are produced by referring to the ordinary 

 treatises embracing both branches of probabilities (the first relating to 

 chances which can be altered only by the changes of entire units or in- 

 tegral multiples of units in the fundamental conditions of the problem ; 

 the other concerning those chances which have respect to insensible grada- 

 tions in the value of the element measured] the present tract has been drawn 

 ut>. It relates only to errors of observation, and to the rules, derivable 

 from the consideration of these errors, for the combination of the results 

 of observations. 



