824 
THE  TROPiCft^L  AGRiCULTURIST. 
[June  r,  1897. 
“ Agro-crudo,  ” however  rich  in  acid  particles,  can 
never  vie  in  this  respect  with  the  same  juice  in  a 
concentrated  form  with  the  “ Agro-cotto,”  in  which 
form  it  enjoys  besides  a great  superiority  over  un- 
condensed  juice  in  durability  and  in  reduction  of 
volume.  This  concentrated  juice  is  prepared  in  the 
following  manner.  It  is  first  of  all  clearified  by  being 
left  to  stand,  then  boiled  in  large  cauldrons  of  tinned 
copper,  one-third  full,  and  the  boiling  liquid  fre- 
quently stirred  with  an  iron  rod  having  its  head 
wrapped  in  common  canvas,  or  in  rags  which  have 
thus  to  keep  the  bottom  of  the  boiler  clear  of  all 
sediment  ; those  necessary  additions  to  the  boiling 
liquid  which  the  constant  evaporation  of  the  aqueous 
particles  renders  expedient  are  supplied  by  smaller 
supplementary  boilers  in  which  the  liquid  is  kept 
sufficiently  hot  to  hinder  any  interruption  in  the 
ebullition  of  the  juice  contained  in  the  large  vessels. 
When  the  required  density  is  obtained,  a point  which 
is  easily  ascertained  through  the  medium  of  the 
citrometer,  it  is  poured  into  vats  to  cool,  and  finally 
drawn  off  through  ordinary  funnels  into  casks. 
The  adulteration  of  the  acid  or  juice  is  facilitated 
by  the  ready  absorption  of  certain  well-known  and 
easily-obtainable  substances,  which  increase  the  weight 
of  the  acid-juice  when  concentrated.  The  most  com- 
monly employed  substances  for  the  purpose  of 
adulteration  are  tartaric  acid,  chloride  of  sodium, 
and  sulphuric  acid.  The  methods  employed  in  Sicily 
in  order  to  detect  the  cheat,  if  not  so  scientific 
and  perhaps  less  accurate  than  those  in  use  in 
England,  are  at  least  inexpensive,  simple,  and  suffi- 
ciently effective.  Citrate  of  lime,  which  seems  to  be 
the  safest  form  in  which  the  acid  principle  can  be 
conveyed,  and  is  the  substance  whence  the  citric 
acid  is  directly  manufactured,  is  now  prepared  to 
some  extent  in  Italy,  although  up  to  within  the 
last  quarter  of  a century  this  preliminary  process 
was  considered  impracticable  from  a remunerative 
point  of  view.  A very  well  known  authority  on  the 
subject  laments  in  forcible  terms  the  remissness  and 
io-norance  of  his  countrymen  in  Sicily,  which  alone 
TTermits  foreigners,  to  reap  that  harvest  which 
Italians  neglect  to  gather  and  garner  for  themselves. 
The  objections  raised  in  bygone  days,  from  the 
supposed  impossibility  of  procuring  at  home  a suffi- 
cient quantity  of  proper  chalk,  have  been  shown  to 
be  utterly  mistaken  wtth  respect  to  the  production 
of  citrate  of  lime.  Objections  of  a similar  nature 
are  now  mooted  with  regard  to  the  production  of 
citric  acid,  and  have  been  partially  disproved  already 
bv  the  establishment  of  a British  firm  in  Messina, 
which  has  undertaken  successfully  the  manufacture 
of  citric  acid  in  conjunction  with  tartaric  acid. 
With  regard  to  the  essential  oil  industry  in  Sicily, 
it  is  said  to  be  both  widespread  and  prosperous. 
Essence  producers  and  exporters  are  numerous. 
The  essential  oils  are  derived  from  all  varieties  of 
the  Citrus  group,  though  they  differ  considerably  in 
quality,  that  expressed  from  Bergamot  being  the 
best  and  then  follow  the  Lemon,  Orange,  and  Citron, 
the  relative  value  of  the  essence  being  in  inverse 
order  to  that  of  the  juices. 
The  mode  of  payment  of  the  workmen  engaged  in 
expressing  the  essential  oils  is  peculiar.  Instead  of 
being  paid  at  a fixed  rate  per  day  or  hour,  or  for 
the  weight  or  number  of  rinds  expressed,  he  is  remu- 
nerated according  to  the  amount  ef  essence  he 
succeeds  in  extracting  out  of  a given  weight  of 
rinds. 
It  is  stated  that,  though  the  bulk  of  the  oil  pro- 
duced in,  and  exported  from,  Sicily  is  quite  pure, 
vet  it  is  sometimes  adulterated  with  other  essential 
oils  and  sometimes  with  turpentine,  or  even  with 
resins.  The  occurrence  of  these  adulterations  seems 
to  have  discredited  and  unsettled  the  market  value, 
BO  that  it  became  necessary,  or  at  least  expedient, 
in  some  cases  to  submit  it  to  analytical  test  before 
exportation.  Owing  to  these  precautions,  the  character 
for  genuineness  of  the  Sicilian  essential  oils  has  been 
redeemed,  or  rather  maintained.— t/o/iii  A.  JacUsoh, 
j{cii;.—  (Jardcncrs'  Chronicle, 
PLANTNG  NOTES. 
Fruit  from  the  Cape. — Since  our  last  report  the 
“fruit  ships”  have  arrived  from  the  Cape;  the 
first,  the  “ Scot  ” bringing  55  boxes  of  Pears  and 
294  boxes  of  white  Grapes;  the  second,  the 
Avondale,  bringing  in  559  boxes  of  white  Grapes. 
We  are  informed  that,  with  the  exception  of  30 
boxes,  these  consignments  turned  out  in  good 
condition,  and  realised  fair  prices.  The  faulty 
boxes  above  noted  were  very  over-ripe,  and  hardly 
saleable. — Gardeners'  Chronicle. 
Longevity  of  the  Larch. — The  Chronique  Acjncole 
du  Canton  de  Vaud  contains  various  records  con- 
cerning the  age  attained  in  Switzerland  by  the 
Larch.  There  are  at  Mayens-de-Sion  two  old  Larches 
which  measure  from  20  to  22  feet  round  the  base, 
and  65  feet  in  height.  Both  are  referred  to  in  a 
plan  of  the  grounds  dated  1546,  where  they  are 
mentioned  as  “ the  two  Larches  before  the  house.” 
They  were  then  a good  age,  and  now  are  351  years 
older.  These  years  do  not  seem  to  have  weakened 
them,  as  they  are  in  full  vigour.  Another  Larch 
is  found  on  the  Alp  de  Torrent,  near  Albinen ; it 
is  called  the  boundary-tree,  as  every  hundred  years 
the  people  of  Albinen  and  Louecheles-Bains  go  out 
to  it  to  re-mark  the  boundary.  On  its  trunk  a sort 
of  niche  has  been  cut  in  the  bark,  and  on  the 
exposed  wood  are  engraven  the  dates  from  1400  to 
1700.  Larch  wood  has  considerable  durability ; 
the  above  journal  mentions  a chalet  at  Loueche-les- 
Bains  where  the  piece  of  wood  which  supports  the 
ceiling  is  of  Larch,  and  bears  the  date  1536. — Garden- 
ers’ Chronicle. 
Insect  Police. — We  take  the  following  extract  from 
an  article  of  Mr.  R.  C.  Perkins,  published  in  a 
recent  number  of  Nature,  p.  499 : — “ The  first  importa- 
tion of  Coccinellidffi  to  destroy  hordes  of  soale-insect- 
in  the  Hawaiian  Islands  was  made  in  1890,  when 
Vedalia  cardinalis  Muls,  a native  of  Australia,  was, 
sent  over  by  Mr.  Albert  Koebele.  At  that  time 
many  trees  were  in  a deplorable  condition  from  the 
attacks  of  Icerya,  Monkey-pod  trees  being  particularly 
badly  infested — so  much  so  that  they  were  being 
largely  cut  down  as  the  only  recourse.  The  Vedalia 
was  a complete  success ; it  became  perfectly  natu- 
ralised, increased  prodigiously  for  a time,  practically 
•leared  the  trees,  and  then,  as  the  Icerya  became 
comparatively  scarce,  decreased  in  numbers,  while 
at  the  present  time  it  is  evident  that  the  number 
of  the  scale  and  its  destroyer  has  arrived  at  a fixed 
proportion.  Previously  to  its  introduction  here  the 
same  lady-bird  had  done  excellent  service  in  the  fruit 
orchards  of  Lower  California In  many  parts  of  the 
islands  the  Bananas  and  Palm-trees  have  been  severely 
attacked  by  the  larva  of  a species  of  Pyralidina. 
There  is  little  doubt  that  in  course  of  time  this 
plague  will  be  entirely  kept  under  by  a fine  Chalcid 
(Chalcis  obscurata.  Walk.),  introduced  from  China 
and  Japan,  which  has  already  multiplied  enormously 
at  the  expense  of  these  caterpillars — so  much  so, 
indeed,  that  in  many  localities  the  trees  have  now 
entirely  recovered.  Again,  within  the  last  few  years 
a Lamellicorn  beetle  (Adoretus  umbrosus)  has  been 
introduced  from  Japan.  This  insect  speedily  multi- 
plied prodigiously,  and  soon  destroyed  nearly  every 
Rose-tree  in  Honolulu,  and  subsequently  attacked 
the  foliage  of  many  other  trees*  The  cultivation 
of  Roses — once  a feature  of  the  city — became  im- 
possible; while  a remedy  seemed  hopeless.  One  day, 
however,  Mr.  Koebele  discovered  a parasitic  fungus, 
and  by  cultivation  of  this,  and  infecting  healthy 
beetles,  soon  spread  it  far  and  wide.  Whether  the 
fungus  will  prove  entirely  effective  is  not  at  pre- 
sent certain,  but  in  any  case  it  will  be  a most  useful 
aid.  The  writer  has  seen  the  ground  under  trees, 
which  were  attacked  literally  strewn  with  dead 
beetles— all  killed  by  the  fungus— and  beneath  the 
surface  of  the  soil  the  larvm  had  likewise  perished. 
It  is  at  least  certain,  therefore,  that  myriads  of  the 
beetles  were  destroyed  very  shortly  after  the  fungus 
was  spread  around  by  the  individuals  that  had  been 
infected.” — Gardeners'  Chronicle, 
