Miss Nightingale must have impressed Sir Bartle Frere as greatly as he had impressed her. He now became one of her constant visitors, and a busy correspondence began between them. He and his family became friends too of Mr. and Mrs. Nightingale, whom they visited at Embley. "There are amongst his papers for 1867 and the five following years considerably more than a hundred letters, short or long, from Miss Nightingale to him, mostly upon sanitary questions affecting India."[92] The letters from him to her are not less numerous. "I will make 35 South Street the India Office," he said, "while this affair is pending." Miss Nightingale took note of his conversations, principally for communication to Dr. Sutherland, but also for her own guidance. But if she had much to learn from him, he also must have found something to learn, and some inspiration to derive, from her. The work which she had done for the Royal Commission had given her a great knowledge of sanitary, or rather insanitary, details in India; and on the principles of sanitation she was an acknowledged expert. Her acquaintance with the official history of the Indian Public Health question was unique, for no other person had so continuously been in intimate touch with it. The clearness of her mind and her breadth of view impressed every one who saw her. And then something must be allowed, in considering her successive "conquests" (as Mr. Jowett used playfully to call them), to the personal factor. The administrators and ministers who sought or were invited to audience of her would have been more (or less) than men if they had not felt a certain pleased curiosity in meeting this famous woman, who rose from an invalid's bed to receive them. Each of them speedily discovered that her enthusiastic devotion to humanitarian causes was equalled by her soundness of judgment, and that remarkable powers of brain were accompanied by all of a woman's graciousness "She is a noble-minded woman," said Mr. Lowe of her, "and so charming." [92] _Life of Sir Bartle Frere_, vol. ii. pp. 38, 39.