7 72 THE POPULAR SCIENCE MONTHLY. 



of these bones are found occasionally in birds, reptiles, and amphibia. 

 We meet a few other marks of the reptiles in the ornithorhynchus: for 

 example, some ribs are partly or wholly separated from the spine ; the 

 hollow called the acetabulum, in which the thigh-bone is attached to 

 the pelvis, is not perfect ; the ear is formed very simply, the audi- 

 tory canal not being wound spirally, and the outer ear being wanting. 



-++<*- 



THE MYSTERIOUS SOUNDS OF NATURE. 



By EOBEET SPRINGER. 



THE author of an essay on " The Empire of Tones," which was pub- 

 lished at Brunswick a few years ago, wrote : "The globe is 

 played upon around its whole circuit by the billows of the mighty 

 ocean ; it is encompassed by the strata of the atmosphere ever mov- 

 ing in sound-waves ; and is swept from pole to pole by a flood of the 

 most diversified tones which have their origin in nature. Over the 

 eternal snow-peaks of the mountains, where all life has long since been 

 made stark by the cold, howl icy storms like the voice of a gigantic 

 organ. In the deep bosom of the earth the miner hears the murmur of 

 the subterranean waters, the whistling of the jets of escaping gases, and 

 the monotonous trickling of the gathered dampness. The human race 

 has heard the voices of creation for thousands of years, from its child- 

 hood ; but how incompetent has science been till now to explain the 

 origin and meaning of these innumerable sounds ! " A notice of some 

 of the most remarkable of the sounds which are produced by the acous- 

 tic forces of nature will be of interest. 



It should be borne in mind that waves of sound produced by a 

 single impulse have the property of putting other waves in motion, so 

 as to prolong the effect and produce a tone from the combination of 

 the wave-movements. From this we may understand how resonances 

 may be caused and harmonies may be heard in nature, the real origin 

 of which may not be perceived by the common observer, or even by 

 the learned investigator. Of such are the mysterious noises heard in 

 the woods of Ceylon, on the banks of the Orinoco, and on the penin- 

 sula of Sinai. The rustle of the woods, the roll of the thunder, the 

 crash of the storm, the murmur of the waterfall all those sounds of 

 the earth and the air of which the poets are so fond, and in which the 

 ancients recognized the prophetic voices of the gods sober science 

 seeks to trace back to the same law whose operation is perceived when 

 the bullet whizzes through the air, when the wind whistles through 

 the crack of the door or window, when the burning wood snaps in the 

 fireplace, when the stove-door crackles in cooling, when the teakettle 

 sings that the water is boiling. Most of these sounds, which are pro- 



