Freezing Cave near Galena, Black Hills, South Dakota. (Miss L. A. Owen, Cave Regions of the Ozarks and Black Hills. Cincinnati, 1898, page 209): “At Galena, a new mining town of golden promise, there is reported to be an Ice Cave, where ice forms at all seasons, and during the warm weather is a source of comfort and pleasure to the miners.”
Windholes in the Ozark Mountains, Missouri.—Mr. H. F. Brinckerhoff, of Aurora, Mo., informs me that there are a number of cold air current caves in the Ozark Mountain region. One of them is some 19 kilometers south of Aurora, Lawrence County, and is used for cold storage in summer. There is a cave in a limestone bluff about 15 meters above a river, and in the rear is this windhole, which is an opening about 30 centimeters high and 3 meters wide. A strong current of air comes out from it in summer, and the hotter the air outside, the stronger is the outward coming current. In winter the current is reversed. The outward current is so strong in very hot weather that a handkerchief held in it is straightened out to an angle of about 45°.
Freezing Cave and Well at Decorah, Iowa. Described in Part I. (Dr. C. A. White, Report of Geological Survey of State of Iowa, 1870, vol. I., page 80. A. F. Kovarik, Scientific American Supplement, No. 1195, November 26th, 1898, pages 19,158, 19,159).
On June 1st, 1869, Dr. White found the ice dry and well frozen, and he thought it was then accumulating. The cave was cool and apparently dry, and no strong air current was passing through.
Mr. Alois F. Kovarik, of the Decorah Institute, has made a valuable series of observations about the Decorah Cave. The temperatures he observed were the following:
| IN THE VALLEY, SHADE. | DIVISION. | LOCUS GLACIALIS. | END. | |||
| July | 1, | 1897 | +33.3° | +2.2° | 0.0° | 0.0° |
| ” | 27, | ” | +21.1° | +5.0° | 0.0° | 0.0° |
| Aug. | 14, | ” | +32.2° | +5.8° | +3.1° | 0.0° |
| Sept. | 3, | ” | +32.2° | +7.2° | +3.1° | +8.3° |
| ” | 18, | ” | +33.9° | +8.6° | +6.1° | +8.3° |
| Oct. | 16, | ” | +24.0° | +10.0° | +8.3° | +8.3° |
| ” | 30, | ” | +10.0° | +7.2° | +4.7° | +5.0° |
| Dec. | 11, | ” | -2.2° | -2.7° | -1.1° | -2.0° |
| Jan. | 8, | 1898 | -0.0° | -2.7° | -3.9° | 0.0° |
| ” | 22, | ” | -5.0° | -6.1° | -3.9° | -3.9° |
| Feb. | 26, | ” | -0.0° | -6.6° | -6.6° | -5.0° |
| March | 12, | ” | +2.8° | -1.6° | -2.7° | -2.7° |
| ” | 26, | ” | +8.8° | -1.7° | -1.6° | -1.1° |
| April | 16, | ” | +25.6° | -1.4° | +1.1° | -1.1° |
| ” | 30, | ” | +13.9° | +1.1° | -1.1° | -1.1° |
| May | 28, | ” | +17.2° | +1.7° | -0.3° | 0.0° |
| June | 9, | ” | +25.0° | +1.7° | -0.3° | 0.0° |
| ” | 18, | ” | +22.3° | +1.7° | -0.2° | 0.0° |
| July | 16, | ” | +35.0° | +7.2° | 0.0° | +2.2° |
On the 1st of July, 1897, a cold breeze was noticed coming from the cave to a distance of at least 30 meters. At the entrance the breeze was strong enough to blow out a candle. This breeze was not noticed at other times. From December to February inclusive, on the contrary, the breeze was reversed. From July to October, 1897, the walls of the cave were moist. From October to February they were dry. In February frost began to appear on the walls. On March 12th, 1898, the walls were covered with frost. The ice appeared at a spot nearly at the end of the cave on the 26th of March, 1898. At a place about 6.50 meters nearer the entrance, however, is where most ice forms. This place Mr. Kovarik calls Locus Glacialis. The ice appeared here about the 29th of May, 1898. It increased rapidly up to June 12th, when it was at its maximum, and was about two meters in width. It generally covers the north wall from top to base. The greatest thickness in 1898 was 29 centimeters.
The temperature which Mr. Kovarik recorded on the 16th of April at Locus Glacialis of +1.1 seems an anomalous one. On writing to him he sent me the following explanation: "April 16th, after I left the thermometer at Locus Glacialis the usual time, I noticed that it registered +1.1° C. It seemed singular, for at both the Division and the End, the thermometer registered considerably lower. I left the thermometer at its place for about an hour longer, and noticed then that it did not register differently. I would suggest this explanation: This is true about water that upon freezing it gives off its latent heat. Now on April 16th some water dripped into the cave on the wall near where the thermometer was, about 1.50 meters from the floor. The amount of water was very small, but as it came in contact with the cold wall it began to give out its latent heat which affected the close by thermometer. The temperature of the rock was without doubt between -1.° and -3°."