Do you know when rum was introduced to this cocktail? I see in Stan Jones' Complete Bar Guide, under "East India Cocktail" (page 274), that Jamaican rum is listed as an optional ingredient. More recently, PDT's Cocktail Books also adds aged rum to their East India, but I haven't found anything before 1977.
Pineapple syrup replaced the raspberry as early as 1888. Both Harry Johnson's 1888 and 1900 New & Improved Bartender's Manuals list pineapple syrup instead of raspberry. Trying to organize my cocktail recipes and the many East India variations is proving difficult. Thank you once again for your research!
Appreciate all the history you publish on your site. I was wondering why my recipe didn't include raspberry syrup, and I realized I had referenced Harry Johnson's 1888 edition of The New & Improved Illustrated Bartender's Manual, in which he replaced the raspberry syrup with pineapple and changed the aromatic bitters from Angostura to Boker's. It sounds better with the raspberry syrup.
Impressive amount of research! I see a Jamaican rum version in the comments, which is worth noting. J.A. Groshusko's 1933 Jack's Manual uses Jamaican rum.