Why is Sherlock Holmes translated as "福尔摩斯" (Fuermosi)?
The term "福爾摩斯" was used in newspapers as a detective example (中國亦有福爾摩斯), as early as 1905.

香港華字日報, 1905-10-25


  Title: 香港華字日報, 1905-10-25 = The Chinese Mail
  Bib ID: NPTCM19051025
  Publisher: 香港 : 香港華字日報有限公司
  Date Created/Published: 1905-10-25
  Page: 7th
  
  


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福爾摩斯譯名及其他

i edited this answer, with sound files of "福", in min nan (閩南話) and cantonese (廣東話). one may compare these with the 1st syllable of english pronunciation of "holmes", have fun 

in min nan (閩南話), according to 教育部臺灣閩南語常用詞辭典:

福　hok　mp3 file

in cantonese (廣東話), according to 漢語多功能字庫, using sydney lau scheme:

福　fuk1　mp3 file