|
|
 At the Arizona-Sonora Desert Museum''s paleontology lab, the air scribe has become the workhorse of fossil preparation. The discovery of a large sauropod dinosaur in the highly indurated sandstones of the Mid-Cretaceous Turney Ranch Formation southeast of the museum posed numerous technical problems for our lab staff. Most troubling was the removal of vast amounts of sedimentary rock, which was both very tough and firmly cemented by silica to the softer, calcite-replaced bones. Experimenting with a number of hand tools, grinders, hardware-store engravers, and rotary devices, we happened upon a Chicago Pneumatic Air Scribe (see supplier''s address on page 421), mccullochchainsawpm610 and it has since become our primary lab tool on this project. We now have five Chicago air scribes, and progress on our dinosaur has been extraordinary. One large mccullochchainsawpm610 and complex midback vertebra, which had been crushed during fossilization, took seven months to prepare with the scribe, but it was in the middle of a 150-pound block of sandstone. Not only was museum preparator Yolaikia Sciole able to remove this complex and fragile vertebra without damage, but ultimately it was prepared from the inside out, exposing most of the internal bone structures, including arterial and mccullochchainsawpm610 nerve canals and never-before-seen pneumatic structures that lightened the bone in life. Most of the bones in this vertebra are no more than 0.25-inch thick and are replaced by easily cleaved, fragile calcite. The air scribe, and a light touch by the preparator, did the trick. However, risks abound even with above-ground tanks. Proof of that is found in the nationwide results of the Farmstead Assessment System (Farm-A-Syst). A decade ago, University of Wisconsin water quality specialist Gary Jackson helped develop Farm-A-Syst into a voluntary environmental audit to help farmers identify potential sources of water pollution. In recent years, some form of the program has been adopted in nearly every state."There have been 120,000 farmstead assessments done nationally," says Jackson. "From those surveys, it''s clear that the most common environmental risk on the farm is the petroleum storage area." Looking for a chainsaw for sale? We have tons of chainsaws to choose from right here! Not only do we have a huge chainsaw selection for you to choose from, our chainsaws are off the chain as far as discounts. We have a huge selection of cheap chainsaws.
|