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Seeing Plants Grow

Seeing Plants Grow image
Parent Issue
Day
29
Month
June
Year
1894
Copyright
Public Domain
OCR Text

In the laboratary the growth of a plant may be rendered visible by attaching a fine platinan wire to the stem or growïng part. The other end of the wire, to vvhich is f astened a pointed piece of charcoal, is pressed gently against a drum. The drum is covered with white paper and kept revolving by clockwork. Of course if the growth is stationary a straight line ia marked on the paper, but even the slightest increase is shown by the iuclined tracing on the paper. By a simple modifloation of this arrangement, the growth of a plant can be rendered audible. The drum must be covered by narrow strips of platinum Eoil, say one-eighth of an inch wide and one-eighth between each strip. If the strips of platinum be made to complete the circuit of a galvanic battery to which an electric bell is coupled up, then the bell will continue ringing while the plant grows an eighth of an inch, followed by silence while the pointer is passing over the space between frwo strips, for the next growth of an eighth of an inch, and so on. The growth of soine very rapidly growiug plante and the opening of some flowers, such as the compass plant, can be heard direct by means of the micro phone. By the above means it has been proved that plaats grow most rapidly

Article

Subjects
Ann Arbor Argus
Old News