Blood Lily (Scadoxus multiflorus)

Public Domain Photo: A visitor photographs a blood lily (Scadoxus multiflorus) at the Fairchild Tropical Garden, located in the south of Miami on an 83-acre site between historic Old Cutler Road and Biscayne Bay. The Garden is internationally renowned for its collections of palms, cycads, and other tropical plants, including many rare and endangered species of plants.

Blood Lily (Scadoxus multiflorus) is also known by names such as Football Lily, Powderpuff Lily, Poison Root, Fireball Lily, etc. The Scadoxus, having close affinities with Haemanthus from which it has been separated only recently, is a genus of 9 species native to tropical Africa. As a garden plant, or indoor plant, it is cultivated in many parts of the world, notably in North America, Europe and some parts of Asia. The plant can live in the most neglected conditions, with the least care. The ideal climate is tropical, and it may not withstand extreme cold conditions. Mostly one bulb produces a solitary bunch of flowers consisting of up to 200 individual flowers in a season, or annually. The size of the flower can be as big as a football, and it is interesting to watch as a stalk may come up from a dormant bulb from below the ground and produce a bunch of flowers, and a few leaves may grow up, mostly after the flowers wither away.

More public domain photos of Blood Lily flowers and a plant with a bud and leaves are below.

Tortoises mating

PD Photo: A pair of tortoises mating in a zoo

Tortoises (land turtles) are reptiles living on land belonging to the family of Testudinidae of the order Testudines. Tortoises vary in size from a few centimeters to two meters. Their lifespan is compared to humans, though there are claims about tortoises in zoos/captivity having lived longer. For instance, in the Alipur Zoological Gardens in India there was an Aldabra Giant Tortoise brought to India by Lord Wellesley in 1875. It was at least 130 years old when it died, though there are claims that it was over 250 years old.

Many species of tortoises are sexually dimorphic. In some species, males have a longer, more protruding neck plate than females. In others the females’ claws are longer than males’ claws and females tend to be larger than males. The male also has a plastron that is curved inwards to aid mating.

Tortoises of some species lay only a single egg, while others may lay up to 30 eggs. For instance Testudo hermanni boettgeri, the Balkan Hermann's tortoise, lays 6 to 10 eggs. Most Mediterranean tortoises lay 5 to 6 eggs per clutch, and they can lay two or more clutches per season.

Incubation of tortoise eggs depends on availability of favorable temperature range (around 30 °C), and for most species incubation takes between 8 and 11 weeks. The lower the temperature the longer it takes, for example, at around 27 °C incubation can take 18 weeks or more, while at 35 °C the mortality rate of eggs/newborn tortoises will be the highest.

A robot based on drawings by Leonardo da Vinci

Photo: Model of a robot based on the drawings by Leonardo da Vinci; photo by Erik Möller, Genie exhibit, Berlin 2005.

Leonardo da Vinci was respected as an engineer, during his lifetime. When he fled to Venice in 1499 he was employed as an engineer and devised a system of moveable barricades to protect Venice city from attacks. He kept detailed notes and sketches of his scientific ideas. His journals include a vast number of notes on inventions, some of which are practical and others found to be impractical. He did not take much pain to conduct experiments or prove scientifically about scientific ideas he noted in his journals. They include musical instruments, hydraulic pumps, crank mechanisms, mortar shells, bridges, flying machines (a helicopter and a light hang glider), mills, levers, hoists, winches, pulleys, gears, lens-grinding machine, hydraulics, war machines, cannons, diving suit, and many more.

The oldest heliographic engraving in the world

Photo: The first known surviving heliographic engraving in the world, made by French inventor Joseph Nicephore Niepce in 1825 by contact under an engraving with the heliographic process.

Niepce’s seminal work was a step towards the first permanent photography taken with a camera obscura, an optical device that projects an image of its surroundings on a screen. It is a reproduction of a 17th century Flemish engraving, showing a man leading a horse. The Bibliothèque nationale de France bought it for euro 450,000 € in 2002, deeming it as a national treasure.

Photography evolved as a result of studies and scientific inventions over many centuries. Long before the first photographs were shot, Chinese philosopher Mo Di described a pinhole camera in 5th century BCE. Ibn al-Haytham (965-1040) studied the camera obscura and pinhole camera, Albertus Magnus (1193-1280) invented silver nitrate, and Georges Fabricius (1516-1571) invented silver chloride. Daniel Barbaro described a diaphragm in 1568. Wilhelm Homberg explained photochemical effect, i.e., how light darkened some chemicals, in 1694. The fiction book Giphantie (1760) by French author Tiphaigne de la Roche described what can be interpreted as photography.

The first permanent photo-etching was an image produced in 1822 by Nicéphore Niépce, but it was destroyed by an attempt to duplicate it. However, Niépce was successful to produce another etching again in 1825 (see photo). He made the first permanent photograph with a camera obscura in 1826. His photographs took as long as 8 hours to expose. So, to find a new process, he worked with Louis Daguerre and they experimented with silver compounds, based on the discovery by Johann Heinrich Schultz in 1724 that a silver and chalk mixture darkens when exposed to light.

Though Niépce died in 1833, Daguerre continued the work and developed the daguerreotype in 1837, and took the first ever photo of a person in 1839 when, while taking a daguerreotype of a Paris street, a pedestrian stopped for a shoe shine, long enough to be captured by the long exposure of several minutes. Later, France agreed to pay Daguerre a pension for his formula in exchange for his promise to announce his discovery to the world as the gift of France which he did in 1839.

Canon Digital Camera IXUS

The Digital IXUS (IXY Digital in Japan and PowerShot Digital ELPH in US and Canada) is a series of ultra-compact digital cameras released by Canon. The first Digital IXUS released in June 2000 fitted the technology of the PowerShot S10 into a body similar to the APS IXUS II. Between 2003 and 2004, starting with the Digital IXUS II, Canon moved from the use of CF cards to SD cards to create thinner cameras.

Canon's PowerShot A and S line of the time were being made as small as contemporary technology allowed. Canon used its experience with small film cameras, particularly the APS IXUS, to mass-produce good digital cameras smaller than anyone else had managed up to the time.