The Meridian Cipher. The Women of the Royal Atlas, #1

Every map tells a story. Some are designed to lie. Miss Corisande Peverell is one of England's finest cartographers, though the map that made Commander Lucan Merrivale famous was largely her work. Once her lover as well as her professional partner, Lucan accepted sole credit when the Crown Meridian Society erased her name-and lost her trust with it. Seven years later, the Society declares Lucan dead in the remote Orsene mountains.
Corisande refuses to mourn him on the strength of another man's report. Hidden inside Lucan's final survey calculations, she discovers a message written in the private cipher they created together:The published route is false. Trust no map bearing Halberd's seal. Certain that Lucan uncovered something powerful enough to make him disappear, Corisande steals the original expedition chart and forces her way into the official recovery party.
But Major Aldous Hest, the expedition's ruthless commander, appears far more interested in reaching an abandoned mountain observatory than in finding the missing man. From the guarded archives of London to Vienna, Constantinople, and the snowbound Orsene passes, Corisande follows a trail of altered measurements, erased roads, and stolen records. Pursued across the roof of a moving train and trapped beneath an avalanche deliberately set in motion, she must rely on the expertise that powerful men have spent years claiming as their own.
Lucan may still be alive-but survival cannot erase betrayal. As Corisande and Lucan race to protect astronomical records capable of exposing a fraudulent border survey, they must confront the desire they never extinguished and the choices that destroyed them. Corisande will not surrender her judgment for love, and Lucan cannot win her back with apologies. He must place the truth-and her name-above the career built upon his silence.
The Meridian Cipher is a sweeping Victorian historical romance filled with secret codes, dangerous expeditions, intellectual passion, action, intrigue, and an emotionally earned second chance. Book One of The Women of the Royal Atlas.