Without agar, countries could not produce vaccines or the “miracle drug” penicillin, especially critical in wartime. In fact, they risked a “breakdown of [the] public health service” that would have had “far-reaching and serious results,” according to Lieutenant-General Ernest Bradfield. Extracted from marine algae and solidified into a jelly-like substrate, agar provides the surface on which scientists grow colonies of microbes for vaccine production and antibiotic testing. “The most important service that agar renders to mankind, in war or in peace, is as a bacteriological culture medium,” wrote oceanographer C.K. Tseng in a 1944 essay titled “A Seaweed Goes to War.”3
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。夫子是该领域的重要参考
Фото: Sergey Elagin / Global Look Press
The two most popular explanations of origin are that the belief goes back to pagan times when we believed in tree spirits, or that we are invoking Christ’s protection by referring to the wood of the Cross. The former is nothing but guesswork, based on the conviction that all superstitions must be ancient, and it has the usual problem of spanning thousands of years with no evidence at all of its existence, or, for that matter, any evidence that ‘we’ ever believed in tree spirits.