260 ANNUAL OF SCIENTIFIC DISCOVERY. 



to the wind becoming north during the continuation of an ozone 

 period or at its termination. According to the observations contained 

 in this paper, the potato and other diseases occur at the same time and 

 appear to be produced by the same causes. As ozone is invariably 

 attendant upon these causes, Dr. Moffatt was induced to try its effects 

 upon vegetable life by means of actual experiments. In August, 1851, 

 two plants were placed under a glass case, so resting upon slips of 

 wood as to permit the air freely to pass beneath and an ozone test- 

 paper was fixed in the crown of each glass. A watch-glass containing 

 a piece of phosphorus was placed upon the soil in the pot which con- 

 tained a longiilora. In the course of ten hours the test-paper became 

 tinged and the interior of the glass was bedewed with moisture. At 

 noon on the following day, or eighteen hours from the first action of the 

 phosphorus, dew drops were perceived to hang from the points of the 

 leaves ; the test-paper in the other glass did not show the slightest 

 change. In two days the leaves began to assume a brownish tinge, 

 and became darker, until nine days after the commencement of the 

 experiment the branches began to droop, and on the tenth the whole 

 plant was completely withered ; the ozone paper was not deeply tinged, 

 less so than was frequently found to be the case in twenty-four hours 

 in common atmospheric air. The other plant continued healthy. 

 The experiment was repeated upon two geraniums with the same 

 result ; that which was exposed to the influence of ozone, although 

 the stronger of the two plants, perished in seven days, whilst the other 

 remained possessed of its vitality and continued to blossom. The 

 principal conclusions arrived at by Dr. Moffatt from the observations 

 contained in his paper are, that the greatest number of diseases 

 occur with decreasing readings of the barometer and thermometer, 

 and with appearance and increase of ozone, that certain diseases 

 would appear peculiar to certain directions of the wind, that epi- 

 lepsy and sudden deaths occur most frequently at the commencement 

 of an ozone period, that the potato disease accompanies the diseases 

 in the animal kingdom, and that atmospheric ozone is injurious not 

 only to animal but to vegetable life. 



ON A PECULIAR PROPERTY OF ETHER, AND OF SOME ESSENTIAL 



OILS. 



THIS property, which has just been made knowq by Prof. Schon- 

 bein, so well known by his discovery of ozone, is similar to that 

 possessed by phosphorus, when put in contact under certain circum- 

 stances with pure oxygen, or of atmospheric air, of developing that 

 powerful oxidising agent, which has received the name of ozone. If, 

 says M. Schonbein, a little ether is poured into a bottle of pure 

 oxygen, or of atmospheric air, and exposed to the diffused light, 

 agitating it from time to time, the ether, after an interval of four 

 months will have acquired new properties. Although it does not act 

 on litmus paper, it decolors the solution of indigo, converts pure 

 phosphorus into phosphoric acid, eliminates the iodine from iodide of 



