i  Notices  respecting  New  Books.  309 
discovery,  that  he  could  recognize  no  other  principle  than  attraction 
in  the  regulation  of  phenomena."  These  words  refer  to  Prop.  XIX. 
of  Book  3  of  the  Principia,  which  contains  what  Mr.  Airy  calls  "  this 
astonishing  investigation,"  adding  that  "  it  is  one  of  the  many  in- 
stances in  which  Newton  has  obtained  a  correct  result  by  means  ap- 
parently quite  inadequate."  This  seems  strange.  It  may  of  course 
be  that  Newton  and  Laplace  are  both  wrong  ;  but  then  it  may  be 
that  Mr.  Ogilby  is  wrong.  Suppose,  then,  we  try  to  ascertain  his 
qualifications  for  discussing  a  difficult  question  by  seeing  how  he 
deals  with  a  comparatively  simple  one.  Here,  for  instance,  is  his 
notion  of  the  effect  of  "  the  centrifugal  force  "  on  a  fluid  in  a  state 
of  rotation.  "The  centrifugal  force  generated  by  rotation  would 
repel  the  fluid  particles  from  the  interior  parts  and  leave  a  vacant 
ellipsoidal  space  round  the  axis,  of  greater  or  less  extent,  according 
to  the  velocity  of  rotation  and  the  density  of  the  fluid  mass  "  (p.  .97); 
from  this  he  argues  that  the  hypothesis  of  the  original  fluidity  of  the 
earth  is  inconsistent  with  itself.  However  this  may  be,  it  must  at 
least  be  allowed  that  according  to  this  beautiful  conception  a  cylinder 
of  the  fluid  coinciding  in  direction  with  the  axis  of  revolution  would 
be  supported  by  nothing,  and  that  this  is  a  view  of  the  effects  of  ro- 
tation which  will  perhaps  find  acceptance  when  the  views  of  Newton 
and  Laplace  are  forgotten. 
Here  is  another  instance  of  Mr.  Ogilby's  powers.  It  must  be 
premised  that  gravity  at  the  equator  is  to  be  represented  by  288  and 
at  the  pole  by  289,  or  more  generally  by  m  and  m+  1.  By  a  process 
of  reasoning  he  finds  (p.  53)  that  the  following  relation  exists  be- 
tween these  numbers, 
That  there  may  be  no  mistake  as  to  his  meaning,  he  enunciates 
this  equation  in  words  printed  in  italics,  and  goes  on  to  state, 
"  this  theorem  enables  us  to  correct  errors  both  of  astronomical  and 
geodetical  observation  in  measuring  the  ellipticities  of  the  earth  and 
planets."  The  reader  will  notice  that  the  above  equation  may  be 
written  thus : — 
{(m+l)2-m2}2  =  0, 
and  that  this  gives,  as  alternative  results, 
1=0  or  577  =  0. 
Need  we  add  that  the  treatise  has  been  written  in  the  interests  of 
true  religion  (pp.  xii,  50,  51,  103,  104)? 
We  have  spent  a  good  deal  of  time  on  this  treatise,  and  have  got 
little  profit  from  it ;  for  we  are  not  psychologists.  Had  it  been 
otherwise,  it  would  have  suggested  many  curious  questions  as  to 
possible  types  of  mind  and  character,  and  we  should  probably  have 
ended  our  study  of  the  book  by  classifying  its  author  with  the 
squarers  of  the  circle. 
