694 
were found to be a square with diagonals of 12 miles, 
and area 72 square miles; ‘ Underground city,’ were 
found to be a square with diagonals of 20 miles, and 
area 200 square miles. The total area of Philadelphia 
is 129 square miles, and, of the built-up portion, 134, 
or ten and a half per cent. Deducting from the 
square representing the ‘ Street-car city’ the salient 
intercepted by the Delaware River, it leaves just the 
same area, or 134 square miles, showing the city to 
have reached the limit of street-car travel. The 
areas benefited vary as the squares of the velocity of 
travel: hence elevated roads would be worth to the 
city four times as much as surface lines, and under- 
ground roads about eleven times as much. Since 1850 
Philadelphia has lost, in population, one-half a mil- 
lion people, equivalent to a revenue, on the real es- 
tate which they would have occupied and improved, 
of about two million dollars per annum. The two 
broad zones of the overcrowded portion of the city 
were also outlined; and the extent of the benefits to 
be conferred by only two lines of elevated roads were 
clearly shown, by diagrams, to extend to the entire 
city. Elevated roads occupy an intermediate position 
in cost of construction, rate of travel, and general 
utility, between surface and underground structures; 
and there can be no doubt that the time has fully ar- 
rived when this city, for her own sake, requires them, 
and should heartily co-operate with any parties so 
proposing to improve and extend her resources. The 
following were some of the conclusions arrived at: 
1°. The city has reached and already surpassed the 
ordinary limits of street-car travel. 2°. The ratio of 
increase of population is rapidly declining, chiefly 
from lack of more rapid and cheaper means of transit. 
3°. The present steam-roads in the city cannot sup- 
ply the demand, as they have surface line trains, which 
must move slowly, and cannot be run at close inter- 
vals: fares are too high, and stations too distant. 4°. 
Camden, N.J., is rapidly gaining population at the 
expense of Philadelphia. 5°. The annual loss to the 
city in revenue, from the cause, will reach millions of 
dollars. 6°. Unless relief is afforded, the city will be 
corralled by time-limits, and the density of the popu- 
lation must increase rapidly at the expense of health 
and morality. 7°. Two lines of elevated railroads 
at right angles to each other, and properly located, 
would benefit an area equal to double that of the 
built-up portion of the city. 8°. The fears of oppo- 
nents of elevated roads, of losses to the city or the 
individual from withdrawal of patronage or depre- 
ciation of property, are shown by experience in 
New York to be groundless. 9°. If Philadelphia de- 
sires to retain even the present low rate of increase 
in population, and high rate of salubrity, she must 
promptly respond favorably to the request of her 
citizens to be permitted to build elevated roads. 10°. 
The limits of the city are not such as to warrant any 
corporation in building an underground road, were 
it recommended or allowed, with any fair prospect of 
returns for many years. —— Mr. William H. Ridg- 
way read a paper upon the action of water in the 
modern turbine, claiming that it is nothing more than 
an improved Barker’s mill, and that there is no such 
SCIENCE. 
[Vou. III., No. 70. 
thing as the water spurting through the shutes, and 
impinging on the buckets, as is generally believed; 
the wheel, on the contrary, taking a velocity very 
much greater than that of the inflowing water. —— 
Mr. J. J. de Kinder presented an illustrated descrip- 
tion of a method of removing condemned machinery 
by dynamite, as practised by him in the case of 
the side-levers of the old Cornish pumping-engine 
at Spring Garden water-works, Philadelphia, which 
weighed twenty-nine thousand pounds each. Dril- 
ling, tapping, and breaking each beam in two, with 
half a pound of dynamite, and without injury to the 
building or other machinery, occupied thirteen hours. 
Even had despatch been unnecessary, it might have 
taken two weeks to do this work by the ordinary 
methods, 
Academy of natural sciences, Philadelphia. 
Botanical section, May 12.— Mr. Thomas Meehan 
referred to his theory that a fasciated branch is due, 
not to ‘over-luxuriance’ of life, but to a degradation 
of vital power, as published before the American asso- 
ciation in 1870. A number of phenomena, conceded 
to result from low vital conditions, were considered by 
him to be inseparably connected with fasciation, the 
essential feature of which is the production of an ex- 
traordinary number of buds, with a corresponding 
suppression of the normal internodal spaces. This 
is precisely the condition of a flowering branch; and 
all its attendant phenomena find their analogue in a 
fasciated stem. Taking the test of vital power as the 
ability to retain life under equal circumstances, we 
find the leaves on a fasciated branch dying before those 
on the rest of the tree. In severe winters the branches 
in the fasciation wholly die in many cases, while 
those on other portions of the tree survive. Pre- 
cisely the same circumstances attend inflorescence. 
The leaves, in their procession from a normal condi- 
tion to petals, lose this evidence of vitality in pro- 
portion to the degree of transformation. The petal 
dies before the sepal, the sepal before the bract, and 
the bract before the leaves, in the general order of ~ 
anthesis in a compound flower; though there are 
cases, where, secondary causes coming into play, this | 
rule may be reversed. In a general way, however, 
the soundness of the point would not be disputed. 
From all these facts in analogy, it might be said that 
a fasciated branch is an imperfect and precocious 
attempt to enter on the flowering or reproductive 
stage. 
Natural science association, Staten Island, 
May 10.— Mr. Hollick read a paper upon recent 
discoveries of Indian implements at Tottenville, de- 
scribing in detail the net-sinkers and hammerstones. 
These latter, according to Mr. Rau, were employed as 
hammers, ‘‘ since they show the most distinct traces 
of violent contact with hard substances.’’ ‘The Tot- 
tenville hammerstones, with two exceptions, are made 
of soft sandstone, evidently with no intention of using 
them upon any hard substance; and there seems to 
be no doubt that in this locality they were used in 
cracking the oysters among whose shells they are so 
