"The air within this chamber will soon be, and indeed is now, worse than that without doors. Come, open the window and come to bed, and I will convince you. I believe you are not acquainted with my theory of colds." Mr. Adams complied with both these requests. He tells us that when he was in bed, the Doctor began to harangue upon air, and cold, and respiration, and perspiration, with which he was so much amused that he soon fell asleep. It does not appear that any ill consequences followed from their breathing during the night the pure air of heaven. THE WRITING AND SIGNING OF THE DECLARATION OF INDEPENDENCE. We happen to know what kind of weather it was in Philadelphia on Thursday, the Fourth of July, 1776. Mr. Jefferson was in the habit, all his life, of recording the temperature three times a day, and not unfrequently four times. He made four entries in his weather record on this birthday of the nation, as if anticipating that posterity would be curious to learn every particular of an occasion so interesting. At six that morning the mercury marked sixty-eight degrees. At nine, just before going round to the State House to attend the session of Congress, he recorded seventy-two and a half degrees. At one, while he was at home during the recess for dinner, he found the mercury at seventy-six. At nine in the evening, when the great deed had been done, the instrument indicated seventy-three and a half degrees. From another entry of Mr. Jefferson's we learn that he paid for a new thermometer on that day. The following are the three entries in his expense-book for July fourth, 1776: "Paid Sparhawk for a thermometer...................£3 15s. Pd. for 7 pr. women's gloves....................... 27s. Gave in charity.................................... 1s. 6d." The price that he paid for his thermometer was equivalent to about twenty dollars in gold; and as Mr. Jefferson was not likely to spend his money for an elaborately decorated thermometer, we may infer that instruments of that nature were at least ten times as costly then as they are now. An excellent standard thermometer at the present time can be bought for five dollars, and the sum which Mr. Jefferson paid in 1776 was fully equal, in purchasing power, to fifty dollars in our present currency.