CAROLUS LINNAEUS (1707- 78)

1735 – Sweden

‘A system for naming organisms by assigning them scientific names consisting of two parts’

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LINNAEUS

Each species is given a two-word Latin name – The genus name that comes first and begins with a capital letter, and the species name, which begins with a lower case letter. The genus name is often abbreviated, and the names are always written in italics or underlined. The Linnaean system has six classification categories – in descending order, kingdoms, phyla, classes, orders, genera and species. Only two are used for naming organisms.

German botanist Rudolph Camerarius (1665-1721) had shown that no seed would grow without first being pollinated. In 1729, Linnaeus wrote in a paper about ‘the betrothal of plants, in which … the perfect analogy with animals is concluded’. He insisted that it is the stamens where pollen is made (the ‘bridegrooms’) and the pistils where seeds are made (‘the brides’) that are the sexual organs, and not the petals as had been considered previously.

As botanists and zoologists looked at nature, or ‘Creation’, there was no way of classifying the animal kingdom depicted in bestiaries of the time but alphabetically; or of distinguishing the real from the mythical.

Linnaeus developed a system of classification. Starting with the plant kingdom, Linnaeus grouped plants according to their sexual organs – the parts of the plant involved in reproduction. Each plant species was given a two-part Latin name. The first part always refers to the name of the group it belongs to, and the second part is the species name.

Linnaeus divided all flowering plants into twenty-three classes according to the length and number of their stamens – the male organs – then subdivided these into orders according to the number of pistils – female organs – they possessed. A twenty-fourth class, the Cryptogamia, included the mosses and other non-flowering plants.

illustration of flower reproductive structures ©

Many people were offended by the sexual overtones in Linnaeus’s scheme. One class he named Diandria, meaning ‘two husbands in one marriage’, while he said ‘the calyx might be regarded as the labia majora; one could regard the corolla as the labia minora’. For almost a century, botany was not seen as a decent thing for young ladies to be interested in.

Linnaeus’s scheme was simple and practical and in 1745 he published an encyclopedia of Swedish plants, when he began considering the names of species. Realizing he had to get the names in place before someone else gave plants other names, he gave a binomial label to every known plant species and in 1753 published all 5,900 in his Species Plantarium.

Believing his work on the plant kingdom complete, he turned his attention to the animal kingdom. In his earlier Systema Naturae of 1735, he had used the classification ‘Quadrupeds’ (four-legged creatures) but replaced this with Mammals, using the presence of mammary glands for suckling young as a more crucial distinguishing characteristic. The first or prime group in the Mammals was the primates, which included Homo sapiens (wise man). His catalogue of animals was included in the tenth edition of Systema Naturae, listed with binomial names.

By the time Linnaeus died it was the norm for expeditions around the world to take a botanist with them, hence CHARLES DARWIN’s famous voyage on the Beagle.

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ANDERS CELSIUS (1701- 44)

1742 – Sweden

‘The temperature difference between the freezing point and the boiling point of water is a hundred degrees’

portrait of ANDERS CELSIUS (1701-1744) ©

ANDERS CELSIUS

The scale was called centigrade but was renamed Celsius in 1969

In the fahrenheit scale introduced by the German-Dutch physicist DANIEL GABRIEL FAHRENHEIT the freezing point of water is set at 32 degrees and the boiling point at 212 degrees. Fahrenheit’s scale has been superseded by the metric Celsius scale, with water freezing at 0degrees C and boiling at 100degrees C

A conversion can be made from Fahrenheit to degrees Celsius by subtracting thirty-two and multiplying this figure by five and dividing by nine.

The kelvin scale is preferred

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JANS JACOB BERZELIUS (1779-1848)

1840 – Sweden

‘An element can exist in two or more forms with different properties’

The various forms are known as allotropes. Graphite, diamond and buckyballs are three crystalline allotropes of carbon.

Berzelius contributed more than just allotropes to chemistry. When DALTON revived the idea of the atom as the unit of matter, he used circular symbols to represent atoms. Berzelius discarded Dalton’s cumbersome system and in its place introduced a rational system of chemical shorthand.

He declared ‘I shall take as the chemical sign the initial letter of the Latin name of each element. If the first two letters be common to two elements I shall use both the initial letter and the first letter they have not in common’.

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ALFRED NOBEL (1833- 96)

1901 – Sweden

  • 1866 – Invents dynamite

  • 1876 – Invents blasting gelatin

  • 1886 – Invents ballistite

  • 1896 – Nobel Foundation set-up to comply with the terms of Nobel’s will

  • 1901 – First Nobel Prizes awarded

A Swede educated in Russia, France and the United States, Alfred Nobel was a chemist who set up a factory to manufacture the relatively unstable nitro-glycerine to serve the civil-engineering market. After a disaster in 1864, Nobel found a way to stabilise the liquid explosive with kieselguhr, which he called dynamite. He went on to develop blasting gelatin, ballistite and a series of detonators.

The success of Nobel’s dynamites was compounded by his holdings in oil, leading to vast personal wealth. He left much of his fortune to funding the establishment of a series of awards, one of which included an accolade for peace.
There was another dedicated to literature, with the remaining three presented for achievements in the sciences. The first Nobel prizes for medicine (or physiology), physics and chemistry were awarded in 1901.

The prizes are awarded annually, according to the terms of Nobel’s will; ‘to those who, during the preceding year, shall have conferred the greatest benefit on mankind.’

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