28 ENOLOGICAL STUDIES. 



COMPARISON OF BRIX AND TEMPERATURE READINGS. 



For the purpose of more ready comparison, certain of the tempera- 

 ture and Brix readings on each vat are brought together in Table I. 

 In arranging this table the readings of temperature and Brix made 

 each morning have been arbitrarily chosen in the belief that these 

 are more properly comparable than any other readings made. While 

 the periods were not exactly twenty-four hours each, they represent 

 the conditions observed in a manner readily comprehensible and use- 

 ful to the wine maker. Unfortunately, the condition and character 

 of the grapes used were such as to greatly mar the value of the Brix 

 or gravity readings on the freshly crushed and sugared must. The 

 grapes were so withered in some cases that the juice was viscous and 

 the spindle could not act properly. By an oversight, the Brix read- 

 ings were not made on vats 11 and 3 on the morning of the second 

 day. But the reading on vat 2 was made, and this, with the readings 

 for the next morning, show the unreliability of these observations. 

 The very striking aberrations of the Brix readings of vats 1, 6, and 8 

 for the first three observations further show that for this experiment 

 none of the Brix readings had any value until after the wine was in 

 full fermentation, thus bringing about a correction of its viscosity by 

 the action of the alcohol formed. All of the first Brix readings except 

 for vat 11 are undoubtedly too low. This reading corresponds fairly 

 well with the sugar and solids found on analysis; and it is further 

 certain that the readings made later, wherein vats 1, 6, and 8 are 

 recorded at 24.5, 24.4, and 25, are too high. The analyses of the 

 finished product do not furnish data to support these readings. Thus 

 it will be plain to practical workers that the use of a spindle for deter- 

 mining the richness of a must has its limitations. In other words, 

 some grapes, and especially wilted Ives, ground and pressed in the 

 ordinary manner, may give a must which can not be read on a gravity 

 spindle. Hence to judge these musts accurately the sample must be 

 prepared so as to obviate this difficulty or the wine maker may be 

 greatly misled. 



In this connection it is well to call attention to data obtained on a 

 large number of samples of Ives which were selected so as to fairly 

 represent the normal crop, crushed by hand, and pressed through a 

 cheese cloth bag. This method gave Brix readings sufficiently accu- 

 rate for all practical purposes. 



A further observation that bears upon this question is that the 

 stirring of these vats was not adequately done before taking the first 

 sample. While the workmen did the best they could with the bar 

 "stomper" usually employed to mix the mass in the vats, the results 

 of the analyses prove that the mixing was not well done. While this 

 error does not affect the result so far as the fermentation of the wine 

 is concerned, it does very materially affect the character of a sample 



