NavList:

Another option to consider: Worsley's Epitome could have been Worsley's Epitome. In the 21st century, if you were planning an adventure and wanted an encyclopedic reference that would fit in the memory of your smartphone, you might merge sections and extracts from various documents and resources into a single pdf, maybe with a purpose-built index. A century ago, an explorer might well have collected together various pages from key documents including required mathematical tables, unique tables that suited the explorer's tastes, and extensive geographic references culled from many works. You take those down to your neighborhood book binder, and you say, "Make me an epitome from all of these pages and resources." Your book binder cuts the pages down nicely and assembles them in a durable binding guaranteed to last for the duration of an antarctic exploration (though not guaranteed to live through a small boat journey in the Southern Ocean). Note: I have no evidence that this is the case; I'm suggesting it primarily to open up the meaning of the word epitome. It doesn't have to be a word from the title of a specific book. 

Agreed that we must not apply a narrow 21st century interpretation to the word epitome.

Shackleton  was planning an Antarctic expedition lasting several years. It is reasonable to believe that he would have assembled as much reference material as he could find.  The Antarctic Manual for the Use of the Expedition of 1901 contains a very large biblography - over 800 entries. Shackleton was third officer on the 1901 expedition so he would have been familiar with this manual.

The manual was digitised by Google but when I looked at Google Books this morning I could not find  the download pdf link. I downloaded the book yesterday but cannot remember where from - you will be able to find it if you want it.