VARIETIES. 
77 
employment  of  sulphur  as  flowers  of  sulphur,  no  abatement  in  its  ravages 
could  be  detected,  I  was  induced  to  employ  a  solution  of  pentasulphide  of 
calcium,  a  diluted  solution  of  which  having  been  found  to  act  in  no  way  in- 
juriously to  the  young  and  delicate  shoots  of  several  plants,  was  applied  to 
the  vines  ;the  object  in  view  being  that  the  pentasulphide  should  be  decom- 
posed by  carbonic  acid,  and  that  4  atoms  of  sulphur,  together  with  the  car- 
bonate of  lime  formed,  should  be  deposited  in  a  uniform  and  durable  cover- 
ing on  the  stems  and  branches  of  the  vines  affected.  Although  but  few 
applications  were  made,  the  stems  became  coated  with  a  protective  deposit 
of  sulphur,  and  the  disease  gradually  but  effectively  disappeared,  insomuch 
that  the  houses  have  been,  and  now  are,  entirely  free  from  any  disease  or 
symptoms  of  infection. 
The  young  shoots  are  in  no  way  affected  by  its  application,  and  the  older 
wood  covered  with  the  deposited  sulphur  continues  exceedingly  healthy. 
The  specimens  exhibited  to  illustrate  the  durability  and  protective  in- 
fluence of  the  deposited  sulphur  were  from  vines  which  in  the  autumn  of 
1851  were  covered  with  the  disease,  but  which  since  the  autumn  of  1852 
have  received  no  further  treatment. 
The  vines  in  the  immediate  neighbourhood,  and  adjoining  one  of  the 
houses,  are  covered  with  the  disease;  but  notwithstanding  their  close 
proximity,  no  indication  of  the  disease  has  at  present  been  detected  in 
either  of  the  three  houses. 
A  solution  of  pentasulphide  of  calcium  is  prepared  by  boiling  30  parts 
by  weight  of  caustic  lime  with  80  parts  by  weight  of  flowers  of  sulphur, 
suspended  in  a  sufficient  quantity  of  water;  heat  is  applied  until  the  solu- 
tion has  acquired  a  dark  red  color,  and  the  excess  of  sulphur  ceases  to  dis- 
solve. The  clear  solution  is  drawn  off,  and  after  dilution  with  water  may 
be  applied  to  the  vines  by  means  of  either  a  sponge,  brush  or  syringe.  A 
saturated  solution  of  pentasulphide  of  calcium  may  be  diluted  with  from  12 
to  20  times  its  volume  of  water  previous  to  beiog  employed. —  Communicated 
by  the  Author. —  Chem.  Gaz.  .from  Proc.  British  Association,  1853. 
Prizes  Proposed. — The  Societe  d'Encouragement,  of  which  M.  Dumas  is 
president,  proposes  to  issue  the  following  prizes : — 
1.  A  prize  of  3000  fr.  to  the  author  of  the  best  work  on  the  nature  of  the 
disease  which  attacks  the  vine. 
2.  A  prize  of  3000  fr,  to  the  inventor  of  the  most  effectual  method  of  pre- 
venting or  destroying  the  disease  of  the  vine. 
3.  Three  prizes  of  1000  fr.  each,  and  six  of  500  fr.  each,  in  favor  of 
authors  of  the  best  works  on  the  following  subjects. 
(1.)  Origin  snd  progress  of  the  disease  :  the  work  to  be  accompanied  by 
charts  illustrating  the  annual  progress. 
(2,)  Discovery  of  a  method  of  sowing  at  will  the  Oidium  or  of  innocula- 
ting  it. 
iS.)  Discovery  of  the  conditions  of  hybernation  peculiar  to  the  Oidium, 
