Pure Air.—It is thus that one correspondent, Brother H. Hansen, of San Diego, Cal., writes us:— “Millions of people are sick all the time just for the want of pure air. Our tight bedrooms are full of poisonous air. Air once breathed is poisoned. The room is shut up tight to keep out the cold, and thus are shut out life and health. Why should not such things be taught in our public schools? In the old days of the log houses, with the big holes in the sides, mankind were strong and healthy. God bless the SIGNS OF THE TIMES.” These things are taught, generally, in public schools, though not sufficient to be practical. At least we should so judge from after results. But the truth is simply and forcibly stated in the above. It has been aptly said that if air were taxed, or if we were charged for it, we should use more. Like all God’s gifts, it is free. Let it in, with its life-giving oxygen.