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of the question to go and look for some diatoms to inspect, 

 we must go and ask the nearest brewer for a little yeast. The 

 hot and busy workman grants our petition, wondering the 

 while at the satisfaction with which we receive what is not 

 enough to leaven a baking for the smallest of fairies, or in- 

 fluence, at least for some time, the wort in which it is floating. 

 Delighted with our prize we hasten home, place a minute 

 portion of it in the animalcule cage, with a small drop of 

 warm wort for it to float in, and we slip it in with eager inte- 

 rest beneath the low power of the Microscope. Here we 

 have at once the first and most curious exemplification of a 

 simple cell. This well-known fungi is called the Yeast Plant, 

 and consists of two parts, the cell wall, composed of a matter 

 called cellulose, and the contents of the cell resembling fat 

 or oil. The notion that Yeast was an organised being, in 

 fact, a living plant, was at first strongly opposed by some of 

 the first men of science. The Microscope, however, has con- 

 vinsed them both of its organisation and vitality ! It consists 

 of globular or egg like transparent cells with a nucleus or 

 spot. To watch its changes with efficiency it must always be 

 mixed with a small quantity of newly-made beer. One hour 

 after it has been added to the wort germination commences, 

 and two buds, or cells, are produced on either side of the 

 parent cell. Eight hours after the plants begin to ramify, or 

 throw out slender fibres, some exploding and emitting a fine 

 powder. In three days pointed filaments with lateral branches 

 are produced. Such are the changes to be seen by the patient 

 Microscopist, who will thus have had an insight into the 

 manner in which the germination and reproduction of the 

 first life form is conducted. There are other forms of Yeast 

 Plant existing under different circumstances, even in the human 

 body ; but as these few remarks are only to call attention to the 

 wonders every-day life may furnish to our Microscopes, they 

 are beyond our reach, indeed, strictly confined to the search 

 of professional or highly scientific men. It may content us 

 to know that the governing laws which influence them, are 

 the same as those governing the common Yeast Plant of beer. 

 Of the same sort of one-celled plants is the fungi, or mildew 

 blighting grapes. " Grapes," says Mr. Harris, "when blighted, 

 are covered with what appears to be a white powder like lime, 

 a little darkened with brown or yellow. These dark spots are 



