T,iE FORMS O 



ATER 



have an example of the " scientific use' of 

 this faculty. Without Imagination vye 

 mi<rht have critical power, but not creative 

 oower, in science. 



11. AllCLIITECTUHE OF L.\Ki: ICE. 



OC. We have thus made ourselves acquaint- 

 ed with the beautiful snow-flowera self-con- 

 structeil by the molecules of water in calm 

 cold air. Do the molecules show this archi- 

 tectural power when ordinal y water is 

 frozen ? What, for example, h the structure 

 of the ice over which we skate in winter? 

 Quite as wonderful as the lloweis of the 

 snow. The observation is rare, if not new, 

 but I have seen in water slowly freezing six- 

 rayed ice-stars formed, and floating free on 

 the surface. A six-rayed star, mm cover, b 

 typical of the construction of all our lake ice. 

 It is built up of such forms wonderfully in- 

 terlaced. 



97. Take a slab of lake ice and place ^it in 

 the path of a concentrated sunbeam. Watch 

 the track of the beam through the ice. Part 

 of the beam is stopped, pait of it goes 

 through ; the former produces internal 

 liquefaction, the latter has no cifi-ct what- 

 ever upon the ice. But the liquefaction M 

 not uniformly diffused. From separate spots 

 of the ice little shining points are seen to 

 sparkle forth. Every one of those points is 

 surrounded by a beautiful liquid llower with 

 six petals. 



98. Ice and water are so optically alike that 

 unless the light fall properly upon these 

 tiowers you cannot see them. But what is? 

 the central spot ? A vacuum. Ice swims on 

 water because, bulk for bulk, it is lighter 

 than water ; so that when ice is melted it 

 shrinks in size. Can the liquid flowers then 

 occupy the whole space of the ice melted ! 

 Plainly no. A little empty space is foim-j I 

 with the flowers, and this space, or rather its 

 surface, shines in the sun with the lustre of 

 burnished silver. 



99. In all cases the flowers are formed 

 parallel to the surface of freezing. They are 

 formed when the sun shines upmi the ice of 

 every lake ; sometimes in myriads, and so 

 small as to require a magnify ing-glass to see 

 them. They are always attainable, but then 

 beauty is ofien marred by internal defects of 

 the ice. Even one portion of the same piece 

 of ice may show them exquisitely, while a 

 second portion shows them imperfectly. 



100. Annexed is a very imperfect sketch 

 of these beautiful figures. 



101. Here we have a reversal of the pro 

 cess of crystallization. The searching solar 

 beam is delicate enough to take the molecules 

 down without deranging the order of their 

 architecture. Try the experiment for vour- 

 eelf with a pocket-lens on a sunny day. 

 You will not find the flowers confused ; they 

 till lie parallel to the surface of freezing. In 

 this exquisite w r ay every bit of the u-e over 

 which our skaters glide in AV inter is put to- 

 gether. 



102. I said, in 97, that a portion of the 

 sunbeam was .stopped by, the JQO and lique- 



fied it. AVhat ia this portion? The dark 

 heat of the sun. The great body of the light 

 wavts and even a portion of the d.irk one* 

 pass thiough the ice without losing any of 

 their heating power. When propeily con- 

 centrated on combustible bo-Jies, even after 

 having passed thiough the ice, their burning 

 power becomes manifest. 



103. And the ice itself may be employed 

 to coneenttatu th'-m. With an ice-lens i:> 

 the polar regions Dr. Bcoresby has often con- 

 centrated the sun's rays so as to make then 

 burn won1, fire gunpowder, and melt lead ; 

 thus proving that the limiting power is re- 

 tained by the rays, even after they have 

 passed through so cold a substance. 



104. By rendering the rays of the electric 

 lamp parallel, and then sending them 

 through a lens of ice, we obtain all the 

 effects which Dr. Scoresby obtained with the 

 rays of the sun. 



12. Tnz Gounca OP THE ARVEIKON. ICE 

 PINNACLES, TOWEIIS. AND CHASMS OF THIS 

 GLACIS:! Di:3 Co:3. PASSAGE TO THE 



MONTANVCRT. 



105. Our preparatory studies arc for tho 

 present ended, and thus informed, let us ap- 

 proach the Alps. Through the village of 

 Chamouui, in 'oavoy, a ri^er rushes which U 

 called the Arve. Let us trace this rivjL-r 

 backward from Chamouni. At a little dis- 

 tance from the village the river folks; one 

 of its branches still continues to Le called the 

 Arve, the other is the Arveiron. Following 

 this latter we corne to what is called the 

 " source of the Arveiron" a short hour's 

 walk from Chamouni. Here, as in the case 

 of the Rhone already referred to, you ara 

 fronted by a huge mass of ice, the end of a 

 glacier, and from au arch in the ice tho 

 Arveiron issues. Do not trust the arch ia 

 summer. Its roof falls at intervals with u 

 startling crash, and would infallibly crush 

 any person on whom it might fall. 



106. We must now be observant. Look- 

 ing about us here, we find in front of the ice 

 curious heaps and ridges of debris, which 

 are more or less concentric. These are the 

 terminal moraine* of the glacier. We shall 

 examine them subsequently. 



107. We now turn to the left, and ascend 

 the slope beside the glacier. As we ascend 

 we get a better view, and find that the ice 

 here fills a narrow valley. We come' upon 

 another singular ridge, not of fresh debris 

 like those lower down, but covered in part 

 with trees, and appearing to be literally as 

 "old as the hills." It tells a wonderful 

 tale. We soon satisfy ourselves that the 

 ridge is an ancient moraine, and at once con- 

 clude that the glacier, at some former period 

 of its existence, was vastly larger than it is 

 now. This old moraine stretches right 

 across the main vf.lley, and abuts against the 

 mountains at the opposite side. 



108. Having passed the terminal portion of 

 the glacier, which is covered with stones and 

 rubbish, we find ourselves beside a very 

 wonderful exhibition of ice. The glacier de 



