Salt from the Earth (1944)

[Applause] [Music] salt is in the Earth and in the sea it is mined from the earth as slabs of clear translucent rock or found crystallized out of the sea as Tiny perfect cu tues nature deposits salt by a process which has been going on for millions of years freshwater streams flowing over rocks little by little dissolve out their mineral particles and carry them to the Sea sometimes a stagnant ocean Bay becomes saturated and as its water evaporates layers of salt crystallize out along its Shores at malagash in Nova Scotia just a quarter of a mile from the Atlantic Ocean is the largest salt mine in the British Commonwealth the deposit was laid down more than 27 million years ago it's more than 100 m long and 400 ft wide by the mine cage it's 12200 ft down to the man-made underground Valley from which the salt has been dug enough salt here to supply the whole world for the next 500 years there are several methods of mining salt one method is similar to coal mining at the top of the working slope miners with a long wall undercutter slice out slabs of Rock 3 ft thick the Drillers follow close behind boring holes for dynamiting when the charge is fired most of the Rock Falls away down the slope afterwards the miners pick off the remaining pieces of loose Rock and the face is cleared for another slice with the undercutter salt miners work in a Topsy Turvy World sometimes the angle of the slope is as great as 70° so that the salt will slide easily to the bottom of the pit here Men shovel the loose salt down through holes in the Rock floor into a corridor which runs below and a scoop shovel drags it to a huge storage pit time out for lunch well seasoned a man who sweated hard at his day's work needs salt to keep going an average human body must contain more than half a pound of it a second method of getting out the salt is by evaporation soft water from dozens of sprays throughout the mine plays on the rock it flows down 800 ft to the Central Lake below when the solution is pumped to the surface and the water is evaporated off it yields crystalline salt there are 2 and 1/2 lb of salt to every gallon that's a lot saltier and more buoyant than the sea Crystal Caves in the depths of the Earth are carved out by the soft water sprays from the jagged rocks that are left Min and the stone then they prepare to work the area a second time by another kind of water process the men who work in the salt mine have one of the cleanest of all underground jobs there's no dripping water here as in a coal mine there are no extremes of heat and coal but 56° is the constant natural temperature underground it's hard work but healthy work salt comes up from the bottom of the mine in rock and powdered form 98 .5% pure large rocks are broken and impure ones are removed powdered salt is filled into bags and loaded in bulk into box cars for all the salt of the malagash mine goes for commercial uses it hardens Machinery gears it helps make paper and Roads it feeds livestock and packs fish for shipping it's used in the smelting of ores of copper and silver and lead the Pol plant at San Ontario uses about 21,000 tons of it a year in the making of synthetic rubber salt is stored in concrete pits which are flooded when saturated brine is needed in the process one ton of salt goes into every 5 tons of finished rubber an essential industrial chemical salt from the earth is a valuable part of the natural wealth of Canada [Music]