Neither Mr. Glaisher or Mr. Coxwell were able to note the exact elevation when they were at their greatest height; but from several circumstances they were convinced that it must have been 36,000 or 37,000 feet, or fully _seven miles high_. Later aeronauts have been inclined to doubt if this surmise can be quite correct; but whether it is so or not is of no great moment, for this great balloon ascent will always stand unrivalled in the history of ballooning. Since that day nearly as great, or perhaps even greater, heights have been reached in balloons; but nowadays those who attempt to ascend to great elevations always provide themselves, before they start, with cylinders of compressed oxygen gas. Then when the atmosphere aloft becomes so thin and rare as to make breathing difficult, they begin to fill their lungs with the life-giving gas from the cylinders, and at once recover. After this perilous voyage Glaisher and Coxwell made several other scientific balloon ascents. They met with various experiences. On one occasion, during a lofty ascent, they lost sight of the earth above the clouds for a while, but, the mist suddenly breaking, they found themselves on the point of drifting out to sea. Not a moment was to be lost, and both men hung on to the valve-line until it cut their hands. The result was a tremendously rapid descent. The balloon fell four and a quarter miles in less than a quarter of an hour, covering the last two miles in only four minutes. They reached earth close to the shore, and were fortunate to escape with only a few bruises, though all the instruments were once more broken in the shock. Mr. Glaisher was able to make many interesting notes of the condition of the winds and clouds at high levels. He observed how frequently different currents of air are blowing aloft in different directions at the same time. These differing winds affect the shape of the clouds among which they blow. High above the ground he frequently met with a warm wind blowing constantly from the south-west; and he believed that it is largely due to this mild air-stream passing always overhead that England enjoys such much less rigorous winters than other countries that lie as far north of the equator. This mildness of our climate has long been attributed to the Gulf Stream, that warm current of the sea which sweeps up from the tropics past our shores. But it may well be that there is besides an “Aerial Gulf Stream,” as Mr. Glaisher calls it, blowing constantly above our heads, which also serves to warm the air, and make our winter climate mild and moist.