CHEMICAL AGENT • FREE TRANSLATOR.ORG • Definition of Chemical agent

... knowing what they are, and then see what that instrument does to them. There is some copper (observe the various changes which it can undergo), and here is some nitric acid, and you will find that this, being a strong chemical agent, will act very powerfully when I add it to the copper. It is now sending forth a beautiful red vapour; but as we do not want that vapour, Mr. Anderson will hold it near the chimney for a short time, that we may have the use and beauty of the experiment without the annoyance. ...

— The Chemical History Of A Candle • Michael Faraday

... its Uses.*—The saliva is a transparent and somewhat slimy liquid which is slightly alkaline. It consists chiefly of water (about 99 per cent), but in this are dissolved certain salts and an active chemical agent, or enzyme, called ptyalin, which acts on the starch. The ptyalin changes starch into a form of sugar (maltose), while the water in the saliva dissolves the soluble portions of the food. In addition to this the saliva moistens and lubricates the food which it does not dissolve, ...

— Physiology and Hygiene for Secondary Schools • Francis M. Walters, A.M.