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SI : SI Unit
The International System of Units, abbreviated SI (for the French phrase Système International d'Unités), is the most widely used system of units. Along with the older cgs (centimetre, gram, second) system, SI is sometimes referred to as the metric system (especially in the United States, which has not widely adopted its use in everyday commerce, and the UK where conversion is incomplete). SI is built on seven SI base units, such as the kilogram and metre. These are used to define various SI derived units. SI also defines a number of SI prefixes to be used with the units: these combine with any unit name to give subdivisions and multiples. For example, the prefix kilo denotes a multiple of a thousand, so the kilometre is 1,000 metres, the kilogram 1,000 grams and so on.
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The system can legally be used in every country in the world, and in many countries its use is obligatory. Those countries that still give official recognition to non-SI units (e.g. US, UK) define them in terms of SI units. It was adopted by the 11th General Conference on Weights and Measures (CGPM) in 1960. (See weights and measures for a history of the development of units of measurement).
Americans frequently spell 'metre' as 'meter', and 'litre' as 'liter'; however 'metre' and 'litre' are the official BIPM names for these units, although the American usage has been approved by the US government. The official US spelling for 'deca' is 'deka', though Americans use the international spelling more often than the American one.
The unit 'gram' is also sometimes spelled 'gramme' in English speaking countries, though that is an older spelling. Several other languages use the American spelling. In written practice only the abbreviated (prefixed) symbols are used, qualifying the spelling issue.
The English language version of the official SI brochure (http://www.bipm.org/pdf/si-brochure.pdf) published by the BIPM uses the decimal point instead of the comma to separate the integer portion of a number from the fractional portion. This indicates that the use of the comma isn't an inherent part of SI, but a part of the language and culture in which it is used in a particular case. In the U.S., the decimal point should be used.
my way?" Before she had time to reply, however, I had her in check.
the right thing, and on Sunday I was terribly near it. Yet that won't do.
Straight to her uncle."
"Only to tell on you--?"
"No, not `only'! To leave.html">leave.html">leave me, in addition, with my remedy.html">remedy."
She was still vague. "And what IS your remedy?"
"Your loyalty, to begin with. And then Miles's."
She looked at me hard. "Do you think.html">think he--?"
"Won't, if he has the chance, turn on me? Yes, I venture still
sister.html">sister as soon as possible and leave me with him alone."
and therefore perhaps a trifle the more disconcerted
she hesitated. "There's one thing, of course," I went on:
Then it came over me that, in spite of Flora's presumable
it might already be too late. "Do you mean.html">mean," I anxiously asked,
If I've been obliged to leave her three or four times,
though she's alone, she's locked in safe. And yet--and yet!"
a new hope. I think he wants to give me an opening.
Last evening, in the firelight and the silence, he sat with me
"And did it come?"
"No, though I waited and waited, I confess it didn't, and it was
sister's condition and absence that we at last kissed for go/good.html">good night.
consent to his seeing her brother without my having given the boy--
quite understand. "What do you mean by more time?"
"Well, a day or two--really to bring it out. He'll then be on
I shall only fail, and you will, at the worst, have helped me by doing,
So I put it before her, but she continued for a little so inscrutably
I wound up, "you really want NOT to go."
.
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