92 



Popular Science Monthly 



What Jack Frost Did with a 

 Fountain of Running Water 



JACK FROST is our deftest 

 and daintiest architect. He 

 builds millions of structures 

 each year and draws other 

 billions of patterns. The prob- 

 lem of being original never 

 bothers him. Each snowfiake 

 is an artistic triumph ; each 

 frosted window-pane is differ- 

 ent in its every detail from the 

 countless billions which have 

 appeared since the beginning of 

 time. No, Jack Frost doesn't 

 bother about patent and copy- 

 right laws. If he were so 

 inclined he could secure a 

 patent on every snowflake that 

 falls. 



The accompanying illustra- 

 tion below shows what he has 

 done in the way of an ice cone. 

 Next winter he will make one 

 in the same place — and make 

 it so it won't infringe on the 

 rights of this one. The ma- 

 terial he worked with here was 



This great stalagmite of ice 

 was formed drip by drip 



a spring which gushed up into a fountain. 

 As the ice formed, the water was raised 

 higher and higher from pressure under- 

 neath until the cone was formed. If it 

 could be examined or if a cross-section of 

 it could be obtained it would probably 

 be found to have a hollow center, 

 growing gradually 

 smaller and smaller 

 in diameter. The fact 

 that the running 

 water had consider- 

 able pressure from a 

 high fountain head 

 and that water will 

 find its level made it 

 possible for Jack 

 Frost to fashion the 

 cone. However, the 

 fountain isn't so 

 important after all. 

 He could do equally 

 well with a stream 

 of water from a 

 garden hose, if it 

 were made to spout 

 upward in the same 

 manner and left long 

 enough in that posi- 

 tion in weather of the 

 proper temperature. 



The cone was formed gradually from circumfer- 

 ence to center until the highest peak was reached 



An Icicle Which "Sprouted" 

 Over Night 



WHO ever heard of an icicle 

 growing upside down? 

 There was one particular icicle 

 which was not contented with 

 the usual order of things and 

 accordingly decided to grow 

 from the bottom up. The 

 water as it fell drop by drop 

 from a faucet one very cold 

 night in Beaufort, North Car- 

 olina, froze before it could 

 travel very far on its journey. 

 Slowly, as the water froze, the 

 icicle grew, and when morning 

 came the "sprout" had reached 

 a height of twenty inches. 



It is interesting to note that 

 the huge "icicles" of rock 

 which are often found in caves 

 of the mountainous districts of 

 the United States are formed 

 in a way that is very much 

 similar to the way this icicle 

 was forrned. Underground 

 streams of water, which carry 

 various kinds of rock in solu- 

 tion with them, frequently empty into a 

 cave at its top. The water dropping 

 gradually from the roof of the cave, 

 slowly evaporates and leaves the rock 

 in its solid form. As drop after drop 

 falls and evaporates, a giant "icicle" 

 of rock is formed which is often made 

 up of many attract- 

 ive colors, though 

 yellow, mellowing in to 

 brown is the most 

 common. Somestalag- 

 mites, as they are 

 called, when the 

 base rests upon the 

 ground, or bottom, 

 of the cave, take 

 hundreds of years 

 to form. Often they 

 meet stalactites (sim- 

 ilar formations with 

 the base attached to 

 the ceiling or high 

 projection in a cave) 

 and thus form a con- 

 tinuous column. The 

 Mammoth Cave in 

 Kentucky contains 

 many specimens both 

 of stalactites and 

 stalagmites. 



