The San Francisco call. [volume] (San Francisco [Calif.]) 1895-1913, 1897-05-08

class condition and excellent order. Partlcu-
lar attention was given the vertical pumps
ana connections, and we ind the cos theie y,
to be $9SO3 This amou MT seemed large d NJ
might well arrest attention, out atter tn
oughly investigating the subject mater o ~!
committee find that the new pump Win us
capacity of l., 500 gallons more per houT than
the old ones is great saving in fuel and Ia Dor
that the cost is reasonable and that the Com,
missioners have made wise ana economical
investment.
Granite bridge and concrete-On Novemb Der
20, 1895, the Board of Park Commissioners
decided by resolution to construct a bridge
across the main drive leading to the new
music grounds and museum An agree ment
was entered into with Gray Bros. TO bulld the
archway according to drawings and specihca.
tions furnished BY Edward swain, archltect at
25 cents per cubic foot. The specifications
were su bsequenty modified by decreasing the
thickness OF walls from nine feet to two and
half feet, at a saving of about $4,000.
After the completion OF the archWay the
Comm issioners advertised for bids from archl-
tects 10 draw plans and specifications Tor
granite and concrete work. On January 70,
1896 the plans of bridge submitted by Messrs
Coxhead & Coxhead, architects, were accepted
and bids were called for for the granite and
concrete work. On July 81, 1896 the bid OF
Alexander McLennon for $27,2 for granite
work was accepted, and Superintendent c.
Laren authorized to confer with McLennon
and make the best terms for concrete work.
On July 81, 1896. contract was en- tered
into with Alexander McLennon to furnish
granite and do the granite work except the
four balustrades and pedestal for statue) and
facing arches of main drive y1aduct Tor the
sum of SIC, 600, granite to be like sample SUD-
mitted On August g. 1896, a second contract
was made with Alexander McLen non Tor gran
lite work to the four ball ustradings above the
main drive viaduct for the sum of SIG 600
The constru ton OF the pedestal was DIS
pensed with at a red uction OF $1216 from Nc
Lemons bid.
On August 1, 1896, the Park Commissioners
entered into contract with Gray Bros. Tor 70
cents per cubic foot for all concrete tounda-
ion work to the main arches, balustrades and
pedestal TO main drive viaduct ana ior all
concrete backing to granite work. On COM
pletion of the concrete work settlement was
made with Gray Bros. on the basis OF measure
ment and computations furnished by Archi-
tects Coxhead Coxhead Tor ~ 24'o3l IL -1oo
cubic feet, amounting to $5527 30.
On January %, 1897. &. L. Grunsky, eng1-
neer, at the request of the Park omm1ssion-
ers, submitted dimensions and estimates in
detail of quantities of concrete. He reports
the quantity of concrete in the finished struc-
ture as %, 943 81 cubic feet subsequently in
creased 10 %, 267. 90 cubic feet, but says his
estimate does not include four small blocks OF
concrete filling, the spaces between the ends
of viaduct and the wing walls not having any
definite data 10 make the computation.
Again, at the request of the Park Commits
Ing engineer, inspected the reports and figures
submitted by Coxhead Il Coxhead ana Z. T..
Grunsky; he also obtained from Lieutenant
Charles l.. Potter, U. S. A. engineer, the basis
OF his calculation. Mr.. Davidsons recompu-
tations give %, 267 .4S cubic feet. The differ
ence OF 763. 43 cubic feet between the meas
ures ana computations of Coxhead d CoIhead
and c. Z. Grunsky he ascribes to the fact that
as the concrete work of the structure had
been finished when Mr. Grunsky made his
measurements, he was necessarily compelled
to take certain surface line of the work for
the con tact surface between the granite and
the concrete, whereas Messrs. Coxhead d
Coxhead had measured the actual line of con-
tact O. every course, and these contacts were
Irregular; that difference OF thickness OF
% inches of the coucre te a. the contact with
tie granite facing would reasonably account
for this 763.43 cubic feet.
With reference to Lieutenant Potter's calcu-
lations, Professor Davidson explained the
great difference with Coxhead d Coxhead,
MI Grunsky's and his own by quoting Lieu
tenant Potter-"that he was simply called
upon to 60 to the park and look over the
bridge work that could be seen and give an
opinion Of the concrete in place at that time;
that he had no authority 10 investigate or