Laterite

Laterite is a soil type rich in iron and aluminium and is commonly considered to have formed in hot and wet tropical areas. Nearly all laterites are of rusty-red coloration, because of high iron oxide content. They…

Saprolite

Saprolite is a chemically weathered rock. Saprolites form in the lower zones of soil profiles and represent deep weathering of the bedrock surface. In most outcrops, its color comes from ferric compounds. Deeply weathered profiles are widespread on the continental landmasses between…

Detritus (geology)

Detritus is particles of rock derived from pre-existing rock through weathering and erosion. A fragment of detritus is called a clast. Detrital particles can consist of lithic fragments (particles of recognisable rock), or of monomineralic fragments (mineral grains). These particles…

Diagenesis (the Petrologic principle)

Diagenesis is the process that describes physical and chemical changes in sediments first caused by water-rock interactions, microbial activity, and compaction after their deposition. Increased pressure and temperature only start to play a role as sediments become…

Flame Test

A flame test is relatively quick test for the presence of some elements in a sample. The technique is archaic and of questionable reliability, but once was a component of qualitative inorganic analysis.…

Silicene is a two-dimensional allotrope of silicon, with a hexagonal honeycomb structure similar to that of graphene

Contrary to graphene, silicene is not flat, but has a periodically buckled topology; the coupling between layers in silicene is much stronger than in multilayered graphene; and the oxidized form…

On the pathology of miner’s lung (1875)

and a history of phagocytosis (and athletic fish flakes)

Weddellite and Whewellite

Weddellite (CaC2O4·2H2O) is a mineral form of calcium oxalate named for occurrences of millimeter-sized crystals found in bottom sediments of the Weddell Sea, off Antarctica. Occasionally, weddellite partially dehydrates to whewellite, forming excellent pseudomorphs of grainy whewellite after…

Leavell, B S. “Thomas Jefferson and smallpox vaccination.” Transactions of the American Clinical and Climatological Association vol. 88 (1977): 119-27 and a few notes

Little Turtle, mentioned in the main article, suffered gout and rheumatism before he died in 1812 Wikipedia says Little Turtle, who also met Washington and Adams, made two trips to Washington,…

Reactive arthritis aka Reiter’s syndrome

Reportedly triggered by everything from food poisoning to bug bites to STDs to hormones (estrogen, relaxin) Mnemonic: Can’t See, Can’t Pee, Can’t Climb a Tree

Chrysiasis

Chrysiasis is a dermatological condition induced by the parenteral administration of gold salts, usually for the treatment of rheumatoid arthritis.  Such treatment has been superseded as the best practice for treating the disease because of “numerous…