A HISTORY OF SCIENCE 



those of Mycoderma vini, etc. This being done, ten 

 of the forty flasks were preserved for reference ; in ten 

 of the remainder, through the straight tube attached 

 to each, some drops of the washing-water were intro- 

 duced ; in a third series of ten flasks a few drops of the 

 same liquid were placed after it had been boiled ; and, 

 finally, in the ten remaining flasks were placed some 

 drops of grape-juice taken from the inside of a perfect 

 fruit. In order to carry out this experiment, the 

 straight tube of each flask was drawn out into a fine 

 and firm point in the lamp, and then curved. This 

 fine and closed point was filed round near the end and 

 inserted into the grape while resting upon some hard 

 substance. When the point was felt to touch the sup- 

 port of the grape it was by a slight pressure broken off 

 at the point file mark. Then, if care had been taken 

 to create a slight vacuum in the flask, a drop of the 

 juice of the grape got into it, the filed point was with- 

 drawn, and the aperture immediately closed in the 

 alcohol lamp. This decreased pressure of the atmos- 

 phere in the flask was obtained by the following means : 

 After warming the sides of the flask either in the hands 

 or in the lamp-flame, thus causing a small quantity of 

 air to be driven out of the end of the curved neck, 

 this end was closed in the lamp. After the flask was 

 cooled, there was a tendency to suck in the drop of 

 grape-juice in the manner just described. 



" The drop of grape- juice which enters into the flask 

 by this suction ordinarily remains in the curved part 

 of the tube, so that to mix it with the must it was neces- 

 sary to incline the flask so as to bring the must into 

 contact with the juice and then replace the flask in its 



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