UIS.  2 
THE  HyEAL  HEW-YOEiC'ER. 
tlio  article  more  palatable.  It  ia  li.ar<l  to  iudTico 
jwoplo  to  eat  a  poor  thing  revolting  to  fbo  tasto, 
e>'i;n  thongh  it  bo  cboap,  while,  on  the  other 
hand,  the  more  delloloua  an  article  ia.  the  more 
it  beeoTueu  a  necessity  i.i  larger  quantiUos  and 
at  comparatively  higher  rates.  Wo  have  an 
illustration  of  this  fact  in  the  onormon.s  quanti¬ 
ties  of  butter  consumed  since  the  establishmout 
of  oreanieriert,  which  have  placed  a  better  grade 
of  bntler  before  eouanmers  than  that  formerly 
nitolo  at  farm  dairies.  If  any  one  doubts  Mio 
assertion,  let  him  note  the  ditTercnce  in  time 
whicli  it  takes  his  family  to  consumo  a  50-pound 
package  of  poor  Htnll  (rightly  named  grease  1, 
and  the  sam«!  nuinlKW  of  pounds  of  a  fancy 
article,  nice  in  texture  and  full  of  delicious 
aroma. 
It  is  with  this  hope  of  improving  the  dairy 
products  of  the  world  that  wc  hail  the  inauguni- 
tioa  of  a  British  Dairymen’s  Association,  and  we 
firmly  buliove  that  its  inllueiico  for  good  will  bo 
folt  in  Amonca.  Wo  shall  look  forward  to  the 
first  Convention  of  British  dairymen  with  intor- 
ost,  and  shall  ho  very  much  disappointed  if 
wo  do  not  find  Bomething^in  tho  addresses  and 
discussions  whicli  will  bo  of  valuo  to  tho  dairy¬ 
men  of  America.' 
PARASITIC  LUNG  DISEASE  IN  CALVES. 
It  has  long  been  kuowu  that  there  are  para¬ 
sites  which  infest  tho  air  passages  and  also  tho 
lungs  of  various  suimal.s.  The  one  best  known 
whioli  infests  tho  lungs  of  calves  is  tho  Sh-ouij;/- 
lux  MitmiruXf  a  small  worm  ono-h.alf  to  one  inch 
loug.  Tho  presence  of  this  parasite  is  not  read¬ 
ily  dotoriniried  as  tlio  Bymi>tom8  at  lirst  are  very 
situUar  U)  those  of  an  or<llnary  oold,  and  tho 
stock  raiser  may  not  be  able  to  detect  tho  iliffer- 
eneo  until  too  late  to  bo  of  service  to  the  animal. 
'J'Uose  |>ara«ito8  appear  to  bo  confined  to  no 
co»mty  or  climate  but  exist  among  domestic  ani¬ 
mals  ovorywboro. 
In  a  late  number  of  the  AgricnUunil  Gazette 
a  veterinarian  in  speaking  of  the  parasites  says 
that  the  av  mptoms  of  tlio  affection  are  not  well 
marked  In  tlio  early  stage  f  auseultation  fur- 
nishoH  absolutely  no  evidouco  of  the  disease,  be- 
oanso  the  mnous  rale  which  u  lieard,  is  common 
Ui  all  alTeoUoris  of  the  lungs  in  whleh  tho  secre¬ 
tion  from  tho  lining  momhrano  of  I  he  bronchial 
tuhcfl  is  increased.  'J'lio  most  characteristic 
symptom  is  a  iveculiar,  dry,  husky  cough,  which 
is  flo  constantly  present  that  the  term  “husk ’’is 
lined  to  distingnisli  tlio  diseaso.  Hometimos  the 
mucus  discharged  from  tlio  nostrils  contains  tho 
oggs  and  embryos  of  the  worm  (Stnmtji/lux 
mtiTunis),  and  now  and  then  full-grown  worms 
are  coughed  up :  but  tho  fact  of  their  clo.se  re¬ 
semblance  to  a  piece  of  wluto  tJiroad  aeooutits 
for  the  little  notice  which  is  generally  taken  of 
them.  After  a  few  weeks  tho  calves  begin  to 
fall  off  in  condition,  tho  cough  becomes  more 
troublesome,  and  some  of  the  weakest  animals 
die.  'The  natui'o  of  the  disease  may  be  deter¬ 
mined  by  post-mortem  examination on  slitting 
up  tho  tubes  of  tire  lungs  tbey  aro  found  to  ho 
lillod  with  stronglcB,  often  twisted  together  like 
a  quantity  of  tangled  thi-ead ;  possibly  the  full- 
grown  worms  may  have  been  expelled  beCoro  tho 
death  of  tho  animal,  in  wliich  case  tho  oxamina- 
tiou  of  the  mucus  of  the  bronchial  tubes  will 
always  settle  Gie  question,  as  numerous  eggs 
aud  young  worms  are  certain  to  Ijo  discovered. 
In  proportion  to  the  strength  of  tlio  calf  will  bo 
the  duration  of  tho  disease.  'I’lie  parasites  only 
remain  for  a  eertaiu  time,  jirohably  two  or  tlireo 
mouths,  on  the  bronchial  tubes,  and  if  tho  young 
animal  has  sullieiont  stamina  to  resist  tlie  debili¬ 
tating  effects  of  tho  constant  irritation  which 
tho  worms  causo,  there  will  be  a  satisfactory 
termination,  but  in  many  Instances  death  occius 
from  exhaustion;  and  if  from  want  of  appetite 
or  from  had  quality  of  food,  nutriment  is  not 
supplied  in  sutiiciont  quantity,  the  deadly  iollu- 
euce  of  the  parasite  is  more  miu  ketl.  Treatment 
of  tho  parasitic  limg  diseaso  includes  lirst,  good  I 
nursing,  tho  cattle  should  be  removed  from  tho 
paslmos  whore  they  contracted  the  disea.se,  and 
whore  they  aro  liable  to  a  constant  iutroduotiou 
of  parasitic  germs,  and  be  jilaced  in  a  slioUered 
position.  As  to  food,  any  nutritive  material 
which  will  tempt  the  appetite  is  good  for  the 
animal. 
Various  medicinal  agents  have  been  uswl,  witli 
doubtful  success— oil  of  turpentine  is  certainly 
tlie  most  clfcclivo  meiliciuo  which  ha.s  been  tried. 
All  average  dose  is  n  tablo-spooiiful  mixed  with 
the  yollcs  of  eggs  well  beaten.  The  quantity 
may  be  given  daily  in  the  worst  oases,  but  the 
majority  of  the  animals  will  not  require  more 
than  three  doses  a  week. 
Indicatiotis  of  tlie  hcnclicial  action  of  the 
medicine  wiU  be  seen  ui  tho  improveuieut  of  the 
aplJoUte  and  oomlitiou,  aud  tJie  ilimiuished  fre¬ 
quency  of  tho  cough.  Tho  advance,  however, 
even  in  cases  which  are  treated  suceossfully,  is 
very  slow,  aud  the  animal  remains  in  an  ema¬ 
ciated  state  for  a  considornhle  time.  Inhalation 
of  chlorine  gas,  tho  vapor  of  catholic  acid,  or  tho 
fumes  of  tar,  aro  advocated  by  some,  but  those 
modes  of  tieatment  are  rather  liazardous;  no 
objection  can  he  offerod  against  the  plan  of  driv¬ 
ing  tho  diseased  animals  about  a  abed,  tho  tloor 
of  which  i.s  iiovetod  wdth  powdered  qnickiimo ; 
tho  dost  causes  coughing,  and  tlius  leads  to  tho 
expulsion  of  many  w’orms,  while  others  are  de¬ 
stroyed  in  their  liahitat  by  mixture  of  tho  lime 
dust  with  tho  mucus  secretion  of  tlio  air-passage. 
There  is  no  objection  to  the  use  of  i<xUdc  of  iron 
in  doses  of  10  grains  every  second  day,  as  a 
tonic;  hut  wo  have  not  fouud  tonic  treatmoiit 
to  be  necessary  whou  tlio  means  used  to  destroy 
the  worms  have  been  successful. 
■♦  ♦  ♦ - 
CATTLE  DISEASES  IN  THE  EAST. 
An  outbreak  of  Oriental  Cattle  Plague  occiured 
oil  .April  20th,  187(1,  at  .Szorncy,  and  was  extin¬ 
guished  on  May  0th ;  tho  diseaso  attacked  tweiity- 
oiio  animals,  of  which  ten  died,  six  were  slanght- 
erod,  and  live  rocovored  ;  Die  prompt  stamping 
out  of  the  disease  is  attributed  to  tho  rapid  ap- 
plicatidji  of  tho  laws  of  1871.  CatGo  plague 
after  lireakiiig  out  in  several  villages  of  tho  Jaffa 
plain  is  now  subsiding.  The  disease  is  said  to 
have  boon  imported  into  tho  district  by  a  tribe  of 
Bedouins,  among  whoso  cattle  it  w’as  prevalent. 
An  outbreak  of  cattle  plague  has  taken  placo  at 
the  quarantine  staGon  Novosieltza.  In  conso- 
qneuco,  all  clttlo  now  there  and  all  which  shall 
be  admitted  will  liavo  to  submit  to  a  quarantine 
of  twenty-ono  days. 
riftiro-Piwuiunnia.  No  fresh  cases  of  this 
disease  have  appearwl  at  Rm  im,  wliere  the  out¬ 
break  took  (ilaco  last  month,  but  as  a  precaution 
tho  animals  in  the  shed  at  the  time  of  tho  out¬ 
break  have  been  destroyed ;  but  it  has  appeared 
in  a  new  district  in  Luceruo. 
Sljc  Ijovscnuui, 
DO  HORSES  REASON  I 
IlKiis;  is  a  good  story  about  a  horse,  wliicli  is 
told  ill  tho  Boston  •louriia'l,  and  we  presume  many 
of  our  readers  could  tiill  as  good  a  one  if  they 
would  ouly  take  the  tune  to  write  it  out  for  pub¬ 
lication,  Huch  notes  on  animal  instinct  or  rea¬ 
soning  jKiwors  arc  always  iaterostiiig  to  old  aud 
young : 
It  would  bo  diftlcult  to  convince  some  people 
that  horses  and  dogs  aro  jiossessod  of  reasoning 
powers,  and  as  dilllcult  to  convince  otliers,  who 
fondly  love  Gjcso  animals,  that  they  aro  unable 
to  reason  from  cause  to  effect.  A  story  comes 
to  us,  well  vouched  for.  which  will  at  least  in 
terest  the  reiwlcr,  if  not  convince  Jiiui  that 
horses  are  possessed  of  more  of  tho  human  at¬ 
tributes  than  ni'Aiiy  people  aie  wont  to  credit 
them  with. 
Among  tho  many  horses  owned  by  the  High 
land  street  railroad  company,  is  one  whicli  used 
to  givo  the  hostlers  a  deal  of  trouble  by  slipping 
his  halter  aud  roaming  at  will  about  the  stable. 
Tho  halter  was,  on  each  occasion,  buckled  on  us 
Gghtly  as  possilile,  Vmt  to  no  piu  jioso,  for  tho 
horse  would  invariably  be  found  half  an  hour 
afterwards  making  a  diguilied  tour  of  the  stable. 
This  became  luonotonous  to  the  hostler,  aud  he 
determined  to  ascertain  the  modus  oporandi  by 
which  Ins  equine  friend  secured  his  liberty. 
Again  the  halter  was  tighGy  buckled  on,  aud, 
taking  a  seal  wlicro  lie  could  watch  his  trouble¬ 
some  cliurgo,  he  awaited  developments.  Pretty 
soon  a  horse  which  stood  bosido  the  troublesome 
one  was  observed  to  poke  his  nose  into  Ids  ueigh- 
bor’s  stall,  and  catching  the  end  of  tho  halter 
htraii  between  his  tooth,  ho  pulled  at  it.  His 
lirst,  second  and  third  attempts  to  unloose  the 
buckle  wore  unavailing,  but  with  a  perseverance 
remarkable  even  in  a  man,  tho  horse  returned  to 
his  work  repeatedly,  and  lUially  out  dropped  tho 
bucklo-tonguo,  the  tliroat-straxi  foil,  and  the 
horse  of  inqiiisiUvo  mind  was  soon  stalking  about 
the  stable  again.  A  cliango  of  location  wao  of 
course  a  iiocessity. 
A  largo,  homely,  jiiobald  gelding,  owned  by 
this  company,  used  to  manifest  a  straugo  regard 
for  a  white  mare  he  formerly  workeil  bosido.  In 
tho  stable  ho  was  hitched  with  a  rope  halter,  and 
until  a  chain  was  substituted,  he  used  to  gnaw 
off  his  halter,  march  delilxiratcly  to  the  stall  oc- 
ciqiied  by  his  mate,  and  squeeze  himself  into 
tlie  stall,  which  was  ouly  large  enough  to  acooui- 
nioUatt!  one  horse  comfortably,  and  a  great  deal 
of  effort  was  required  to  separate  the  equines 
after  they  had  become  wedged  in  so  closely. 
■■  ■*** - 
Tuk  interest  in  speedy  horses  among  tho 
Kussiaus  has  been  in  the  ascendency  for  several 
years  jiast.  As  in  many  other  branches  of 
industry,  in  the  breodiug  of  stock,  they  bid  fair 
to  hecoiiie  formidable  rivals  to  many  of  the 
nations  who  have,  in  times  past,  gazed  upon 
them  with  considerable  contempt.  The  groat 
English  Jockeys  should  begin  to  look  to  their 
lam'cls. 
iuiii  Slscful. 
SOMETHING  ABOUT  THE  SUCTION  PIPE. 
Ahout  throe  couluries  an<l  a  half  before  the 
advent  of  Christ  the  versatile  mind  of  Auistutle 
was  led  to  investigate  the  marvels  presented  by 
the  action  of  tho  syringe,  wutor-bcllows,  siphon 
and  other  primitive  hydro-] mouraatio  contriv¬ 
ances.  **  Natiiro  ahliors  a  vacuum,”  was  Gic 
opigrammatio  dictum  of  Gio  prince  of  philoso¬ 
phers  in  explanation  of  the  phenomena.  Tho 
saying  hail  all  tho  essentials  for  ready  and  last¬ 
ing  acceptance.  ’Twas  iioctically  tigurativo,  had 
an  attractively  sciontilic  ring,  yet  was  easily 
explainable,  pleasantly  shelved  one  mystery 
by  subslitiiGiig  another,  but  above  all  it  was 
couveidenfly  short  and  axiomatic..  Accordingly 
for  about  twc>  tlionsauJ  ycai's,  it  was  received, 
oven  by  tbe  learned,  as  clcoi'ly  solving  tlio 
problem  it  only  confused,  and  even  to-slay  it 
often  drops  glibly  from  Gig  lips  of  many  a  pro- 
tenGous  dunderhead  equally  ready  to  sham 
knowledge  by  quoGng  tho  formuIsM  of  exploded 
errors,  or  by  prating  about  Gio  laws  of  modern 
scioncoH  with  w^hoso  forniulus  alone  tho  charlatan 
has  even  a  chance  aenpuiiiitanue. 
About  a  linndred  years  after  Auistotuk’s 
death,  f'TKsics  of  .Alexandria,  invented  tho 
valve  pump ;  and  straightway  Gio  Stagirito’s 
maxim  offered  an  explsnatiou  of  tho  action  of 
Giis  novel  contrivance.  This  consisted  of  two 
single-acting  solid  pistons  moving  up  and  down 
in  two  vortical  cylinders  Inaviug  bottom  valves 
only.  Tho  discharge  pi[)e,  furnished  with  an 
outgoing  valve,  was  placed  between  tho  jiiston 
aud  the  valve-seat,  so  that  this  oiigiiial  device 
differed  hut  little  from  some  of  otu’  modern 
force  pumps.  The  next  two  tliousand  years 
were  nearly  wasted,  so  far  as  concerned  eitluir 
imiirovciuouts  in  pumps  or  tho  atlaiiimoiit  of  a 
more  correct  concopGon  of  tho  phllosoiihy  of 
their  working.  Tlio  insm  tion  of  a  valve  in  tho 
pistoii-lioad  and  the  location  of  this  below  the 
discharge  pipe  were  tho  chief  iinprovomonts,  and 
adapted  the  pump  for  lifting  as  woll  as  auction, 
but  moanwliilo  Aui.STori,E’H  dictum  had  acquired 
tho  sacroilnoss  of  a  dogma. 
Tho  mighty  rovolntiou  of  the  Kith  coiitnry, 
however,  was  au  upheaval  of  [ihilosopliical  as 
well  as  theological  siiperineunibeiit  creeds,  and 
Gio  veueralile  Uioory  of  piimiiing  was  soon  sub¬ 
jected  (o  irrovoreiit  acrntiny  like  other  doctrinos. 
Ill  1(511  thero  was  set  up  in  the  firand-DUcal 
water-works,  at  Florence,  a  pump  whoso  suctioii- 
pijio  extended  nearly  sixty  feet  above  the  surface 
of  tho  reservoir.  Despite  its  honorable  locaUon, 
repeated  trials  failiKl  to  raise  water  in  the  tube 
to  tt  greater  bight  than  about  32  feet.  The 
HuperitiUmdcnt  of  tlie  water-works  appealed  to 
bis  felliiw-clU/.en  Gai.ii.eo  to  account  for  tliis 
Ihxuid  obstinacy.  Totally  blind  and  nearly 
deaf,  jicrseoutod,  oiglily  and  moribund,  the  ven¬ 
erable  philosoplicr  could  only  say,  imiiromptu, 
that  Nature’s  ahliorrence  of  a  vacuum  must  bo 
iiiOiierativo  above  tho  lught  of  32  foot.  A  few 
months  later  he  died  and  his  discqilo  aud 
auiaimensis  ToiiuiCEnni  continued  to  investigate 
tho  iiroblem  whose  niistudied  solution  by  his 
friond  must  havo  been  unsatisfactory  even  to 
that  fnoud  liimsolf. 
Hitherto  tlio  beliof  in  vogue,  ovoii  among 
scletiGsts,  iiad  ascribed  tho  ascent  of  water  in 
an  exhausted  tube  to  a  mysterious  property  in 
nature,  somewhat  analogous  to  that  of  tho 
loadstono  or  gravity.  This  resisted  all  attempts 
to  mako  a  v.acuum  witli  tlie  same  force  it 
employed  to  destroy  it  wlien  made  by  urging  tho 
next  siihstaiicft,  if  a  lluiil,  into  the  void  it 
abhorred.  Analogously  suction  was  regarded  as 
au  occult  faculty  of  tho  numth  that  attracted 
liquids  to  it  iudepeiidently  of  any  extiamous 
iutlUGiico. 
It  was  not  until  1(!13— two  years  after  Gai.i- 
i-Ko’fl  death — that  Tokuioei.li  exploded  these 
veuerablo  error's  by  dcnioiistraliiig  that  atinos- 
jilierio  pressure  was  the  motive  force  in  both 
cases,  and  tliat  pulsion,  not  traction  was  tho 
method  of  its  action.  Having,  by  dint  of  his 
own  reasoning  or  at  Gai.ii,e<i’.s  suggestion, 
reoeticd  tlie  conclusion  that  the  liight  Gi  which 
water  rose  in  an  exhausted  tube  depended  on 
tho  relative  weight  of  the  aqueous  column 
hisido  tho  pipe,  and  that  of  Gie  aerial  pressiiro 
on  the  water  outside  of  it,  it  occiuTcd  to  him 
that  tho  truth  of  this  theory  would  ho  demou- 
stnitcd  If  a  oolunm  of  another  llqiiiil,  the  spociiic 
gravity  of  which  was  known,  were  sustained  in 
a  tube  at  a  bight  proporlloiiod  to  its  gravity. 
Mercury  is  a  Irille  over  j  times  heavier  than 
water ;  the  length  of  a  column  of  this  metal 
therefore,  sustained  by  atmosplioiic  pressure  in 
an  exhausted  tube,  would  be  somewhat  less  Gian 
times  Uiat  of  a  column  of  water  under 
similar  conditions.  At  tbe  sea  level,  in  lair 
weaUier,  atmospheric  pressure  amounts  to  about 
15  pounds  to  the  square  iuch.  Tills  Is  equal  to 
counterbalancing  a  oohimn  of  wator  of  tho  same 
diameter  about  33  feet  high,  and  Toukioelli,  by 
a  very  ingenious  experiment,  proved  that  it  could 
also  sustain  a  column  of  mercury  about  2'J  inches 
ill  bight;  ami  Guis  demonslratod  Gie  tnithof 
his  proposlGon. 
This  discovery,  wliicli  ojieiiod  the  way  to 
scieiitiOo  researches  extoiuliug  far  beyond  the 
special  question  that  hail  originated  it,  iimt  with 
tho  acrimoiiiomt  oppo.sitioii  whicli  always  con¬ 
fronts  all  oxposiu’us  of  the  chei'ishcd  nrroi's  of 
manliind.  Tlio  most  ingenious  objection  urged 
that  Nature’s  abhoiTonce  of  a  vacuum  extended 
to  moroury  as  well  as  to  other  (liilds,  and  that 
Toiuui’ELI.i  had  merely  ili.Hcovercd  Uiat  tUo  force 
of  Giis  abhorrence  varied  with  the  specilio 
gravity  of  different  liquids.  Four  years  later, 
just  one  year  after  Toutttci;r,i,i’s  death,  this 
objecUou  was  clearly  refuted  by  l*Aai'Ai,— the 
celebrated  French  niatliematlclan  and  divine — 
who  had  voriliod  and  varied  ToiiuirKM.r’H  experi¬ 
ments. 
As  tho  lower  strata  of  air  snpjiort  tho  weight 
of  all  those  above  thorn,  Pascal  argued  that 
iitmoH]jhoric  iwossuro  must  bo  greater  at  the 
foot  of  au  elevation  than  at  any  point  In  its 
ascent,  and  consequently  that  the  length  of  a 
Uiiid  column,  if  really  couiitorbalanrod  by  this 
pressiu'o,  must  bo  less  at  the  lop  than  at  tho 
bottom  of  a  monutaiii.  This  crucial  test  was 
niado  with  mercury  in  KllH,  on  the  Puy  do  Dome, 
tho  highest  mountain  in  I’l'anco,  aud  was  decisive 
of  the  corroetnoss  of  I'asi'al’h  inference  and 
TmiunucLLi's  discovery.  Tho  school-hoy  of  to¬ 
day  suiilcH  at  tho  scientific  ignorance  of  tho 
pliUosophers  of  earlier  nges,  of  tho  accumulated 
rcHiilts  of  whose  genius  and  labors  lie  is  tho 
tliouglitless  inliei'itor,  aud  evt-ti  tho  omniscient 
sclioobgii'l  Hckiiiiu  dniums  of  tho  vast  amotint 
of  talent,  reseiircli  and  experimout  needed  to  ex¬ 
plain  correctly  tho  w’orldiig  of  so  simple  a  thing 
as  tlio  suction  pump. 
- - 
A  CHAPTER  ON  GAS. 
“New  Yokk,”  says  a  writer,  “hums  ahout 
1,200,000,000  cubic  feet  of  gas  per  anuum ; 
Chicago,  400  000,000;  St.  I.oiiis,  260, 000, 000 ; 
Cincinnati,  400,000,000  ;  PittHliiirg,  200,000,000  ; 
Han  Francisco,  2.')0,000,000,  and  lialtimoro,  400,- 
000,000.” 
“  How  do  they  make  gas?” 
“  First  they  put  about  two  bushels  of  bitn- 
miuous  coal  in  a  long  air-tiglit  iron  retort. 
Tliis  retort  is  heated  red  hot,  and,  of  course, 
Gio  Coal  is  heated  red  hot,  wlieu  the  gas  bursts 
out  of  it,  as  you  see  it  burst  out  of  lumps  of  soft 
coal  when  on  tho  parlor  llro.  The  gas  passes 
Off  through  pipes.  A  Gm  of  coal  will  make 
10,(1(10  cubic,  feet  of  gas.  Tho  gas  as  it  loaves 
Gio  coal  is  very  impure.” 
“  How  do  they  purify  it?” 
“  First,  w'hilo  hot,  it  is  nm  off  iuto  another 
buikliug :  thou  it  is  forced  throngli  long  per¬ 
pendicular  pipes,  sun'ouuded  with,  cold  water. 
Tills  cools  tho  gas,  when  a  good  deal  of  tar  con¬ 
denses  from  it  and  luiia  down  to  tho  bottom  of 
tho  pciiiQiidicular  pi])es.  This  tar  is  tho  orduiaiy 
tar  which  you  see  boiling  m  tlio  streets  for 
walks  aud  roofs. 
They  now  wash  the  gas.  They  call  it  scrubbing 
it. 
Tills  is  doiio  by  filling  a  large  vessel,  which 
looks  like  a  poriMiiidioular  steam  boiler,  half  full 
of  wood,  laid  crossways.  Then  Gui  Uiousaud 
stroanis  of  cold  croton  wator  aro  HpmGid  through 
this  boiler.  Through  the  mist  and  rain,  and 
between  tlio  wet  sGcks  of  wood,  the  gas  passes — 
coming  out  washed  and  cleansed.  Tlio  ammonia 
condenses,  joins  tho  wator,  and  falls  to  the 
bolGitn.” 
“  What  next  ?” 
“  Woll,  next  the  gas  is  purified.  It  is  passed 
tliroiigii  vats  of  liiim  and  oxide  of  iron,  which 
takes  out  tile  carbonic  acid,  sulpiiuretod 
hydrogen  and  anunouia.” 
“  Wliat  next  ?” 
'•  The  gas  is  now  pure.  It  is  passed  through 
the  big  station  nieler,  then  through  the  iiiaius 
ami  ]/ipes,  till  it  reaches  the  gas  jet  in  your 
room.  Then  it  Imrns,  wiiile  you  all  scold 
because  it  don’t  burn  better.” 
- - - - 
EXCELLENT  INTEREST  RULES. 
J''ou  finding  tho  interest  on  any  principal  for 
any  number  of  days.  Tbe  answer  in  each  case 
being  in  cents,  separate  tho  two  righi  Land 
figures  of  the  answer  to  exiiress  it  in  dollars  aud 
cents : 
Four  per  cent.— Multiply  by  the  number  of 
days,  and  divide  by  72. 
Six  jior  cent.  Multiply  by  tho  unmber  of  days  ; 
separate  the  right  hand  figure,  and  ilivido  by  G. 
Eigtit  jior  cent.— .MulUpfy  by  the  number  of 
days,  and  divide  by  46. 
Nine  tier  cent. — Multiply  by  tlio  number  of 
days;  separato  tho  right  iiaud  tigure,  and 
divide  by  4. 
Ton  per  cent.-  -Multiply  by  the  number  of 
days,  and  dmde  by  35. 
Twelve  per  cent.— Multiply  by  tbe  number  of 
days,  sejiarate  the  right  hand  tigure,  and  divide 
by  3. 
Fifteen  per  cent.— Mnltiidy  by  Gio  mmibor  of 
days,  and  divide  by  24. 
Eighteen  per  cent.— Multiply  by  number  of 
days ;  soiiarale  right  hand  ligure,  and  divide 
by  2. 
Twenty  per  cent.— MulGply  by  tho  number 
of  days,  and  divide  by  18. 
