viii. PREFACE. 



much valuable help in supervising and correcting 

 the manuscript of this work for the Press, as also 

 for her assistance during its passage through the 

 printer's hands. Without her kind offices, I fear it 

 would have been much more imperfect in every 

 way. 



I also owe to Mr. Miller Christy a debt of 

 gratitude for the help he has so ungrudgingly given 

 in preparing the manuscript of this Catalogue for the 

 press, as well as for the trouble he has taken in 

 making the needful business arrangements for bring- 

 ing it before the public. In both these respects, his 

 technical knowledge has been of the greatest possible 

 service to me. 



I am duly sensible of the imperfections, literary 

 and scientific, of this work, and would ask my critics 

 to bear in mind that it has been prepared largely from 

 my own notes, with few opportunities for visiting the 

 Metropolis, and in intervals snatched from the engage- 

 ments arid demands of a busy professional life. 



HENRY LAYER. 

 Head Street, Colchester. 

 February, 1898. 



