THE TECHNOLOGIST. [Sept. 1, 1864. 



84 ON THE PHYSICAL SCIENCES WHICH FORM 



The sea, in like manner, is the great fountain of a rare and prized 

 substance, iodine, but were we compelled to take it directly from the 

 ocean we should require to evaporate tons of water to keep a single 

 photographer supplied with it, and it would be more costly than gold. 

 But the seaweeds employ it as well as the photographers, and have long 

 anticipated the physicians in taking it internally. Day by day they sip 

 a homoeopathic dose of iodine and retain it, and by-and-by we burn 

 them into kelp, and extract iodine and much else that is valuable from 

 the ashes. 



To take another example, phosphate of lime, a minute constituent of 

 all fertile soils and of most waters, is of great value to the ivory turner, 

 the manure-maker, the potter, the silver-assayer, the drug-manufacturer, 

 the dyer, and the lucifer-match maker. It reaches all of them in the 

 shape of the bones of dead animals ; dead cattle from our farms, dead 

 horses from the Pampas of South America, dead walruses from the 

 arctic icebergs, dead whales from the Pacific Ocean, dead men even 

 from fields of battle. Land and sea plants have, as it were, milked this 

 essential constituent of their frames, drop by drop, from the breast of 

 Nature. Animals of all classes, from the lowest to the highest, have 

 robbed plants of their bard-gotten gains, and made their bones strong 

 with the precious substance. Finally, the chartered robber man has 

 robbed them all, claiming even the relics of his brethren, and obtaining 

 in a handful of bone-dust the phosphate of tons of rock and water. 



The industrial importance, however, of plants and animals, as col- 

 lectors and harvesters of valuable mineral matters, is insignificant com- 

 pared with their value as manufacturers of bodies whose worth depends 

 much more on their construction or composition than on their raw 

 material. In their fomier capacity, living organisms resemble simply 

 filters with apertures of different fineness, and fitted to arrest and detain 

 certain substances in themselves valuable. In the latter, those organisms 

 resemble highly complex machines, able to convert the most familiar 

 things into substances precious almost solely from the workmanship 

 bestowed upon them. 



Take for example that important substance, wood. Its chief ingre- 

 dients, charcoal and water, are uncostly and abundant ; but in them- 

 selves they are useless to the carpenter, and he cannot change them into 

 timber. So he calls to remembrance that his great grandfather planted 

 an acorn, which has turned its first small capital to so excellent account 

 that now it is a timber merchant on a large scale, and will contract with 

 you to build a ship of war out of oak of its own making. It is with 

 other trees as with this ancestral oak. Each, with its republic of in- 

 dustrious roots and leaves, is a joint-stock company with limited liabi- 

 lity, engaging to furnish you with pine-stems for masts, fir-wood for 

 planking, logwood for dyeing, cork bark for tanning, walnut for tables, 

 rosewood for picture-frames, willow for cradles, mahogany for wardrobes, 

 ebonv for will-chests, elm-tree for coffins. 



