Arm & Hammer Brand Soda Ad Poster 1900 Postcard

" Colour lithograph advertising poster. Sodium bicarbonate or sodium hydrogen carbonate is the chemical compound with the formula NaHCO3. Sodium bicarbonate is a white solid that is crystalline but often appears as a fine powder. It can be used to experiment and is not very dangerous. It has a slight alkaline taste resembling that of washing soda (sodium carbonate). It is a component of the mineral natron and is found dissolved in many mineral springs. The natural mineral form is known as nahcolite. It is found in its dissolved form in bile, where it serves to neutralise the acidity of the hydrochloric acid produced by the stomach, and is excreted into the duodenum of the small intestine via the bile duct. It is also produced artificially. Since it has long been known and is widely used, the salt has many related names such as baking soda, bread soda, cooking soda, bicarbonate of soda. Colloquially, its name is shortened to sodium bicarb, bicarb soda, or simply bicarb. The word saleratus, from Latin sal æratus meaning "aerated salt", was widely used in the 19th century for both sodium bicarbonate and potassium bicarbonate. The term has now fallen out of common usage. Clowns are comical performers, stereotypically chraacterised by their grotesque appearance: coloured wigs, stylistic makeup, outlandish costumes, unusually large footwear, red-nose, etc., who entertain spectators by acting in a hilarious fashion. The types of their acts varies greatly. Although some find clowns to be scary, their intended purpose is to entertain people, especially young children. Peter Berger writes that "It seems plausible that folly and fools, like religion and magic, meet some deeply rooted needs in human society." A circus is commonly a travelling company of performers that may include acrobats, clowns, trained animals, trapeze acts, musicians, hoopers, tightrope walkers, jugglers, unicyclists and other stunt-orientated artists. The word also describes the performance that they give, which is usually a series of acts that are choreographed to music and introduced by a "ringmaster". The traditional circus is held in an oval or circular arena called a ring, which has tiered seating around its edge. In the case of travelling circuses this location is often a large tent which is nicknamed the "big top".