208 
Book  Reviews. 
J  Am.  Jour.  Pharm. 
|      April,  1909. 
BOOK  REVIEWS. 
Wellcome's  Photographic  Exposure  Record  and  Diary  1909. 
Wellcome's  Photographic  Exposure  Record  and  Diary  for  1909  con- 
tains a  number  of  new  and  interesting  features. 
The  article  on  exposure  contains  a  large  amount  of  definite  infor- 
mation condensed  into  28  pages.  This  is  secured  by  confining  atten- 
tion to  points  which  are  of  real  importance  to  the  photographer  in 
practice. 
The  illustrations  which  have  been  a  feature  of  the  book  from  its 
first  publication,  and  which  have  been  of  such  practical  service  in 
helping  the  photographer  to  make  due  allowance  for  his  subject  in 
exposure,  are  now  conveniently  grouped  together  on  a  card  carried 
in  the  wallet  of  the  book. 
Other  items  in  this  section  of  the  book  are  the  tables  of  Expos- 
ures for  Interiors,  Exposures  in  Telephotography,  Exposures  for 
Copying  and  Enlarging,  Exposures  for  Moving  Objects,  Exposures 
for  Night  Photography,  and  the  well-known  list  of  plate  speeds, 
brought  right  up  to  date  and,  as  usual,  the  most  complete  list  of  its 
kind  available. 
Wellcome's  Photographic  Exposure  Record  and  Diary  is  suit- 
able for  use  in  all  quarters  of  the  globe.  Its  power  to  calculate 
exposure  correctly  has  been  tested  in  every  continent  and  in  every 
latitude,  from  arctic,  temperate,  subtropical,  tropical,  to  antarctic. 
For  the  convenience  of  users  in  different  parts  of  the  world,  three 
editions  are  issued :  The  Northern  Hemisphere  Edition,  for  all  coun- 
tries north  of  the  Tropic  of  Cancer.  The  Southern  Hemisphere  and 
Tropical  Edition,  for  all  countries  south  of  the  Tropic  of  Cancer. 
The  United  States  Edition,  for  use  in  the  United  States  of  America. 
When  purchasing,  care  should  be  taken  to  specify  which  edition  is 
required. 
