190 GRAPE CULTURE AND 



little round globules. Several of these globules are usually 

 attached, and form a string in appearance when magnified, 

 much resembling a string of beads. The sulpur in this shape 

 exposes less surface than could be produced in any other 

 form ; so that with equal fineness, ground and irregular par- 

 ticles would better answer our purpose. To demonstrate 

 this practically, two samples of the same sulphur accurately de- 

 termined in weight, one ground and the other sublimed, were 

 exposed to the same heat as if in the vineyard. Samples 

 selected for this purpose were of apparent equal fineness. 

 The same were weighed from day to dciy, and the experiment 

 repeated several times ; and the above conclusions were am- 

 ply born out in every weighing. Not only did the sublimed 

 or flowers of sulphur evaporate less ; but it also showed a 

 more rapid formation of sulphuric acid than the ground sam- 

 ple, thus furnishing another objection to the use of sublimed 

 sulphur ; one which its exponents have frequently and incor- 

 rectly urged against the use of ground or triturated sulphur. 



I have yet to know of any considerable damage done to 

 vines by the sulphuric acid existing as an impurity in the com- 

 mercial article, either ground or sublimed ; though some have 

 strongly urged the presence of sulphuric acid as an objection 

 to ground sulphur. This is wrong, as there is every con- 

 dition to favor the formation of sulphuric acid in the operation 

 of subliming sulphur, and nothing to favor such formation 

 in the grinding process. Specialists who have made this mat- 

 ter a thorough study, corroborated my conclusionSi 



I do not urge this as an objection to the use of sublimed 

 sulphur, but if any disadvantage accrues from the presence of 

 sulphuric acid, it must not be laid at the door of the ground 

 sulphur.* 



In connection with this let it be known that neither sublim- 

 ing nor grinding does in any wise alter the chemical nature of 



"The presence of considerable quantities of sulphuric acid may be detected by 

 the lumpy condition which results from its presence. 



