Percival Lowell: An Afterglow is the name Miss Leonard gave to the book she wrote about Lowell after his death, which some have interpreted as her long-postponed declaration of her undying love for him. Published in 1921, the book is full of hidden treasures. The brief poem on its first page speaks volumes:

The words on the first two lines reveal his initials (PL) followed by hers (WLL), written together at last.

On the next two lines are the initials of two of Lowell’s assistants, Elizabeth Langdon Williams and John Kenneth McDonald, who assisted in the search for Planet X (Pluto); both were close friends of Miss Leonard.

The next to last line reveals the initials of Lowell’s wife Constance Savage Lowell, though written in reverse (LSC), followed by one terse concluding line.

Constance Savage Lowell

It is of interest to compare Miss Leonard's book to another book written about Percival Lowell after his death, this one by his younger brother Abbot Lawrence Lowell, president of Harvard University. In this detailed biography about the astronomer, his devoted secretary Miss Leonard is not mentioned at all!

This was not an oversight; Miss Leonard had worked for Percival Lowell longer than any other employee, and Abbot Lowell contributed regularly but discreetly to Miss Leonard’s support in her later years. Most likely the omission was in deference to Lowell’s widow, who always considered Miss Leonard to be a rival for her husband’s affection, and even after his death, sought to erase Miss Leonard from his life.