PREFACE TO FOURTH EDITION 



Our Formulae and Methods Manual has been prepared from information 

 acquired by our Chemical Room Staff over the course of more than 25 

 years. The first, second, and third editions were prepared and edited 

 by Oscar W. Richards. The first edition was published as a supplement 

 to The Collecting Net on August 30, 1930. It contained 12 pages of 

 information on biological solutions, stains, buffers and photographic 

 solutions. The second edition, containing additional information on 

 the above subjects, was published on August 27, 1932. The Formulae 

 and Methods Manual was completely revised and published as the third 

 edition by Oscar W. Richards in 1936. 



During the past 15 years more information regarding artificial 

 sea water, buffers, and other biological solutions and formulas has been 

 obtained by our staff. This information has resulted in publication of 

 The Fourth Edition. This edition contains a complete revision of the 

 sections on buffers, artificial sea water, and photographic solutions. 

 Several new tables have been added. It is interesting to note that the 

 material on biological stains has remained practically unchanged during 

 the years. A table of contents has been added for quick references. 



The editor wishes to express his thanks to J. D. Ostrow for his 

 work on Chapters 2, 3, 7, 8 and 9; to Mary Kapp for her work on stains; 

 to J. B. Russell for his assistance on buffers; to A. Bickel for his 

 work on primary and secondary standards; and to E. B. Harvey for her 

 work on the artificial sea waters. 



G.M.C. , 1954 



