Condition Continued: The white inside covers and end papers are all very clean as well. The condition of the pages is also very good. I'm not finding any conspicuous creasing, no placeholder creases. Nor are there any markings. No attachments. And no one has written their name or anything else anywhere in the book. You can't do much better. 
The dust jacket is in pretty nice shape, 1955 has gotten to be quite a long time ago. I can personally attest to that. You can see the dust jacket in the first few photos. The coloring on the spine has faded to a lighter hue. There is only light wear and a few spots along the edges. The jacket is mostly quite clean, particularly impressive given the white coloring of the rear cover and flaps. The flaps are, in fact, perfectly clean. They are also free of wear. There are tiny clips at all four corners. However the price is not touched. I have always had this book in a protective cover.

Henry Regnery Company, Chicago, 1955. Hardcover in Dust Jacket. Letters of  Baron Friedrich von Hügel. Edited with an Introduction by Gwendolen Greene. Preface by John B. Sheerin. First of this edition (SD). 'A Thomas More Book To Live'. 
John Sheerin writes in the Preface: 'Certainly it can be said that no man has written so luminously as Friedrich von Hügel of the spiritual transfiguration that comes to a soul through the Mystical Body of Christ.'
From the dust jacket: 'When Baron Friedrich von Hügel began this correspondence with his niece toward the latter part of his life, he had become one of the outstanding British Catholic scholars and  Gwendolen Greene was a married woman. These Letters, however, are written with the kindly wisdom of an old uncle dealing with the young niece, guiding her by word of mouth and by letter. The Letters are written in a graceful, almost delicate style, in simple and picturesque language. In them he explains to his niece why she needs the Catholic faith. It is a superb apologetic in operation, a presentation in the simplest and easiest terms of the Catholic case to non-Catholics. Through the warmth, the deep humanity and profound spiritual insights of these letters we can almost trace the narrative of her conversion, though her actual reception into the Church took place two years after the date of the last letter. Gwendolen Greene writes in her Introduction: 'Some of these letters have been published already in the Selected Letters of  Friedrich von Hügel, others have not yet appeared in print. They are now collected and issued separately for those people to whom the larger book may be a difficulty-- the people who are not interested in the more directly philosophical and theological sides of religion. Out of all our doings and cares, our hopes and fears, and loves, my uncle makes a little home where the Spirit of Christ can dwell, and where, united to God by prayer, our souls can live and expand.' 
Also from John B. Sheerin: 'Though he disclaimed the role of apologist, his ambition was to gain for the Catholic Church a position of honor and acceptance among the learned men of England. Since his death in 1925, he has been frequently bracketed as one of the three giants of British Catholic scholarship.'