Se ee 
2 
: 
i oh, Seeman 
PROCEEDINGS 
OF 
THE NATURAL SCIENCE ASSOCIATION 
* 
OF STATEN ISLAND. 
VOL. IX, No 4. 
The regular monthly meeting of the 
Association was held at the residence 
of Mr. Lester W. Clark, New Brighton, 
with the president in the chair. 
The following were elected to active 
membership : 
Dr.S. A. Blan, Port Richmond. 
Mr. Lewis Denton, West New Brigh- 
ton. 
Mr. L. W. Freeman presented copies 
of a series of rain gauge charts, show- 
ing the records made by a Draper’s 
self-recording pluviometer for the three 
heaviest rainfalls of 1903, and, after ex- 
plaining the way in which the instru- 
ment works, read the following paper : 
THE EXCESSIVE RAINFALLS OF 1903. 
As the excessive rainfalls of 1903 
were remarkable in regard to their 
number, rate and duration, and as the 
facts here presented are the results of 
instrumental measurements and _ per- 
sonal observations, I have deemed it 
advisable to put them in such a shape 
that they can be made a record of this 
Association. 
Without going into the history of re- 
liable rainfall measurements, the sub- 
ject may be introduced by stating that 
for years it had been the aim and ob- 
ject of the writer to have an instrument 
installed on the Borongh Building that 
would automatically register the rain- 
fall. 
FEBRUARY 13th, 1904. 
In a report to our fellow-member, 
Commissioner of Public Works Louis 
L. Tribus, on the status of affairs in 
the Bureau of Sewers, dated Jan. 31st, 
1902, it was recommended by the writer 
that such an instrument be purchased 
and set up. Commissioner Tribus 
promptly approved of the measure, and 
in September, 1902, the instrument was 
installed and has been in operation 
since that time. 
Subsequently, Deputy Commissioner 
of Water Supply, George S. Scofield, 
also a member of this Association, had 
a similar instrument installed at the 
pumping-station at Tottenville, and to— 
day there are in this Borough, two 
Draper self-registering pluviometers, 
that automatically record, to the 100th 
of an inch in quantity, and tothe 12th 
of an hour in duration, the rainfall in 
their respective localities. 
The objects and uses of an instrument 
of this character are, first: To deter- 
mine the amount of rain that falls dur- 
ing a given time; which fact, taken in 
connection with the amount of storm 
water discharged by water courses, 
sewers, etc., during the same time, as 
determined by gauging of such water 
courses and sewers, furnishes what is 
technically known as the ‘‘ run-off,’’ 
an important and necessary ta 
the designing of sewetaiot (ee Ying er 
sizes and grade 
