98 1STUJ)IKS ON FERMENTATION. 



" Every variety of pcnicillium" said M. Trecul, " especially 

 when young and vigorous, is amenable to transformation into 

 ferment. This is the way in which I operated : I had some 

 little flasks of 30 c.c. to 40 c.c. (about I5 fluid ounces) 

 in capacity, filled quite full with wort, or, at least, con- 

 taining very little air, closed perfectly air-tight with corks 

 which I had kept for a quarter of an hour in boiling water. 

 These flasks when corked were heated to 60° C. or 70° C. (140° 

 to 158° F.). After they had cooled I uncorked them, and intro- 

 duced into them the spores which had been prepared as follows : 

 I placed on a piece of glass some spores of the variety of peni- 

 cillium that I wished to study, taken with a pair of forceps 

 from a mouldy lemon, and I mixed these spores with a drop 

 of wort and observed them under the microscope to assure 

 myself that they contained nothing of a foreign nature ; then 

 I poured my drop of wort from the piece of glass into one of 

 the flasks, which I recorked and laid down. The transforma- 

 tion into ferment took place next day." 



Provided with these new data we set to work again and pre- 

 pared a series of little flasks which were filled quite full with 

 hopped wort, or contained but very little air, as M. Trecul had 

 recommended. These we heated in a hot water bath to 70° C. 

 (158° F.) at least ; we then impregnated them, observing the 

 necessary precautions, which we described at the commencement 

 of this paragraph — not working in the evidently defective 

 manner in which M. Trecul had done. Taking his spore-seeds 

 from a field of sporanges exposed to the air, and afterwards 

 manipulating them, in contact with the air, in water on a 

 piece of glass, before he made his microscopical examination, his 

 experiments were conducted under circumstances in every way 

 conducive to the introduction of causes of error. One of the 

 most serious of those causes is that which results from the sub- 

 stratum of the spores as taken from a mouldy lemon. If M. 

 Trecul will examine under the microscope the water in which 

 any lemon has been washed — even a sound lemon, unattacked 

 by any fungoid growth — he will immediately see the cause of 

 error to which his method of working exposes him. Germs of 



