202 
POPULAR SCIENCE REVIEW. 
ASTRONOMY. 
Transit of Venus in 1874. — As we anticipated, Mr. Stone, Astronomer 
Royal at the Cape, does not accept the result deduced from the observations 
of the last transit by the Astronomer Royal for England. He has, in fact,, 
obtained from the same series of observations, dealt with in a different 
manner — that is, interpreted differently — a solar parallax of about 8"*89, 
corresponding to a mean distance somewhat less than 92 million miles, or 
less than the result obtained by Sir G. Airy by nearly million miles. At 
a recent meeting of the Astronomical Society it was stated that Capt. 
Tupman had obtained precisely the same result as Mr. Stone by a particular 
interpretation of the observations made in December 1874. It is not, how- 
ever, to be inferred that on this account Capt. Tupman either accepts Mr. 
Stone’s estimate, or entertains any doubt as to the validity of the result 
obtained, nominally by Sir G . Airy, but in reality by himself, from the British 
transit operations of 1874. On the contrary, Capt. Tupman’s announcement 
was intended as a jocular way of intimating how little reliance could be 
placed on Mr. Stone’s estimate. But certainly the joke was one which told 
in two ways ; and in the minds of those who are not prej udiced in favour 
either of Mr. Stone’s views or Sir G. Airy’s, will be held to show that 
almost any value between the limits of about 91 £ million and about 941- 
million miles can be obtained from the observations, according to the manner 
in which they are interpreted. 
Distribution of the Fixed Stars in Space. — Mr. Sidney Waters has con- 
tributed a valuable chart to the proceedings of the Astronomical Society,, 
representing the results of Sir J. Herschel’s star gauges of the Southern 
Heavens, given in his Cape of Good Hope observations. The chart is on the 
equal-surface projection. The map was divided into 20 minutes in R.A.,, 
and 3° in P.D. ; and the results of the gauges figured in their proper places ; 
the areas of the spaces were calculated, and the average of the gauges falling 
on each space multiplied by its area, the result being dotted as nearly as 
possible equably over the space. Nearly all the spaces were covered in this 
way ; but in those cases where no gauges fell the average of the surrounding 
spaces was taken. The number of stars marked in the map is very small 
compared with the number actually existing, but the chart represents with; 
sufficient accuracy the distribution of stars over the Southern Heavens down 
to the faintest stars visible in Sir John Ilerschel’s 18^-inch reflector. The 
stars visible to the naked eye were afterwards added. “ The teaching of the 
chart,” says Mr. Waters, “does not confirm the results of Mr. Stone’s investi- 
gations, published in the 1 Monthly Notices ’ of last March. The great massing 
of stars in parts of the Milky Way, its complicated form, and the sudden 
decrease of stars at its borders, are facts not consistent with the view that 
we are merely looking through an immense depth of stars, or that distance 
is the principal reason of their faintness. It is not denied that brightness is 
an important factor in the determination of stellar distances ; but the point 
contended for is that it is not a sufficient basis upon which to found any 
theory of the construction of the heavens. The fainter stars increase at a 
far greater rate than would be the case if Mr. Stone’s view were correct 
