As to my lecture-room, etc., all work stopped for near a month, including the fortnight or more when I was away; and now (September 11) all has been clatter and hurry for the last week or so, and they really seem determined to fulfill the terms of their contract, to finish by the 15th instant. They cannot do that; but I trust the workmen may go out with the month. These cares of building have sadly interferred with scientific work all summer. I have accomplished very little of what I intended. I attended, and, when the last year’s president retired on delivering his address, presided over, the American Association for the Advancement of Science, twentieth meeting, at Indianapolis, capital of the State of Indiana,--a journey of forty-eight hours, in very sultry summer weather, over long stretches of country. I broke the journey by a day in New York, to see two sons of Mr. Darwin just as they landed, and by a three days’ stay, including Sunday, with my old friend Mr. Sullivant, in Ohio. The meeting was a pleasant, though not especially interesting one. I met botanical correspondents of many years’ standing whom I had never seen. At the close we were invited to make an excursion to the Mammoth Cave in Kentucky, which I counted on seeing. But I found that the excursion was to be an overcrowded one.... So I hastened homeward, and was with Mrs. Gray at Beverly Farms, where she had been passing holidays at Mrs. Loring’s at the paternal homestead on the seashore,--a place that you have heard us talk of not a little. It is delightful. I know nothing to give you so good an idea of it as the Devonshire coast, there being plenty of wood quite down to the water. Were we there now, Miss K. and Charles Loring would, I know, charge me with messages. I must tell you that the Scientific Association is invited to meet at San Francisco, California, next summer; and that we have fixed the meeting there conditionally, that is, in case the Californians care enough for our presence to transport a certain number of our representative men free of cost, or nearly so, across the wide continent. If not, we are to meet on the northern part of the Mississippi,--at Dubuque, Iowa, far enough west in all conscience, but a place from which we may easily reach the Falls of St. Anthony and Lake Superior. I must needs attend, as I shall have a retiring address to deliver. And though I can ill spare the time or afford the expense, yet Mrs. Gray and I are longing to see California. What say you and Mrs. Church about joining us for your next summer’s vacation? The mountains which form the sides of the Yosemite Valley will hardly offer as many kinds of flowers as the alpine turf of the Riffelberg, but they may be more novel to you.... * * * * * On December 15, 1871, Dr. Gray wrote to President Eliot, after describing formally the completion of the new buildings, and something of the history and arrangement of the department, the following letter: