MICROSCOPIC GARDENING. 



13 



seeds properly sown and tended by the highly trained experts of 

 to-day. 



Brewing, in the broad sense of fermentations of wine and 

 other spirituous liquors as well as beer — is still carried on in a 

 most primitive way by savages, and even by other peoples. Not 

 to dwell on the manufacture of pulque, palm-wine, &c, where the 

 saccharine juices of plants are merely exposed to the action of 

 any spores that may be floating about in the air, trusting to the 

 particular one needed being in sufficient abundance, or growing 

 with sufficient rapidity and vigour in the liquid, to oust all 

 others — passing over these cases, I say, the manufacture of wine 

 and beer has for centuries been a more or less hap-hazard 

 affair, just as that of mead used to be. But of late years two 

 sets of events have rendered the application of the methods of 

 microscopic gardening necessary especially to the brewers of 

 beer. One was the discovery that certain faults in beer — in 

 some cases destructive diseases — are due to weed-yeasts making 

 their way into the vats and driving out the yeasts that do the 

 necessary work, and the other was the hope of raising varieties 

 or races of the yeast -plant which should give a better beer. 



Pasteur long ago called attention to the fact that foreign 

 germs — i.e. weeds in the sense of my theme — cause diseases in 

 beer, and Reess and others showed that there are various kinds 

 or species of yeast ; but it is to the genius and industry of the 

 Danish zymotechnologist Hansen that we owe most of the 

 numerous discoveries of weed-yeasts and of various species and 

 varieties which produce beers of very different quality. 



The interest of all this to us at the moment is that these 

 results were got by the rigorous practice of the methods of micro- 

 scopic gardening — by isolating a single cell of the particular 

 yeast to be studied, growing it singly on a specially prepared bed 

 kept free of microscopic weeds, and growing from this single 

 cell a pure crop so large that it could be put into the mash-tub 

 and its beer-producing qualities tested. 



This is not the place, nor have I the time, to enlarge on this 

 subject ; but microscopic gardening operations applied to yeasts 

 are spreading rapidly, and affecting the baker who wants good 

 yeast for his bread, the housewife who wants it for her pastry, 

 as well as the brewing industry all over the world. 



To horticulturists, however, -ihese matters do not appeal so 



