It is best to put them into wide-mouthed bottles with glass stoppers, as they are all hygroscopic, that is, sensitive to moisture.
When fresh they contain considerable water, and at all times are hygroscopic.
Usually wood contains not only hygroscopic moisture but also more or less free water in the cell cavities.
Caustic potash and soda are hygroscopic and samples should be weighed at once or kept in a well stoppered bottle.
hygroscopic′ity; Hygrostat′ics, the art of measuring degrees of moisture.
The degree of wind, temperature, and hygroscopic conditions of the atmosphere.
It is not hygroscopic, and may be soaked in water without being at all affected by it.
Now, these styles are hygroscopic—that is, they are influenced by changes in the condition of the atmosphere as regards moisture.
The chaff and awns of all are hygroscopic; that is, are changed by differences caused by variation of moisture in the air.
In general, however, the hygroscopic moisture necessary to saturate the cell walls is termed the "fibre saturation point."
hygroscopic hy·gro·scop·ic (hī'grə-skŏp'ĭk)
Readily absorbing moisture, as from the atmosphere.