Carll. ] 22 |May 4, 
pared. Slight errors necessarily creep into every profile—by the change 
in engineers employed ; and consequent mistakes in benches and level 
points, which often are not plainly marked or described in the notes as they 
should be ; by local alterations of track or change in position of depots not 
always carefully noted ; by alterations at junctions and crossings made by 
one road and not recorded by the other ; and by clerical errors in copying 
and working up the notes and profiles. . 
In making these adjustments considerable time has been spent in the 
field in ascertaining the relation levels of depots, crossings, benches &c. At 
Pittsburgh, Allegheny City, Freeport, Parker’s, Franklin, Oil City, Irvine- 
ton, Titusville, Corry, Union City, Erie City, Girard and other places, and 
in every case more or less variation has been found, relatively, in the points 
given—comparing them as they now are and as they were when originally 
established. These sources of error cannot now be eliminated without a care- 
ful re-leveling of the railway lines, which manifestly isan impossibility un- 
der the circumstances. It only ramains for us to make the best practical use 
we can of the materials at command. As we have shown that they aresome- 
what defective it would be folly to pretend to work out these hypsometric 
elevations to the decimal part of a foot. We shall not attempt it but aim 
only to establish the levels of some of the more important points in this dis- 
trict within a foot or two of the truth which is near enough for all practical 
purposes. 
A 
The first line considered will be from Pittsburgh to Lake Erie by the 
Allegheny Valley, Bennett’s Branch, Philadelphia & Erie, and Buffalo, 
N. Y & Erie Railways. 
Above 
ocean 
Pittsburg Us. Depot... . . - ACceptedvelleyvaitlionm s,m ue lepeu meine 745 
Red Bank Junct....../] 106 |Above Pittsburgh by A. V. profile (I)| 851 
ee ne De st ea Oo am tac ocean by Bennett’ s Branch HELA) | 
4 f vec Uwe 19 |'Too low on U3 
Misvincoyorl Tibhar & Wb i5 6 37 Below Red bank Junct. by B. Branch pro-) 
rite UL CIN, Vs RED ROSE Sis a aoa ee EOE 
oe ean TY ates Vote tes 795 Aboveocean by P. & E. profile (Note tolV) 
x Std) Piece tie Ina te | 19 |Too low on P. & E. profile 
Emporium Junc......./| 208 | Above Driftwood June. by P. & E. profiel 
eu sence \) (Aden “COX ) Sf oo, ect esos tee | 1022 
% Bs Saeki ee LOOS |Above ocean by P. & E. profile (do.) 
oe ss A ooes. cae a LOOT B.N.Y.&P.' TO: al) 
es e Fae Wie pte fay Wl) Too Low on P. & E, 
rs . Sd By Sa 1) IBSEN nics es 
Qlean Crossinie ss. 2358 414 Above Emp. Junct. by B. N. Y. & P. pro- 
TUE OZ GB) Oise eel ets Oc, Aa SS as ucGekemon cach 4 1436 
or es -. ». «| 1488 |Above ocean by N. Y. & Erie profile (Jer-, 
| sey City datum) 
oy S -s. . .. |.1485 |Aboveocean by B.N.Y.&P. “ 
ee We Simtel Om ae 2 Too high on N. Y. é Erie ee 
os : .he wan eres 1|_“ low 
UGLY CCE RGR OMAR OL Glo 6 .| 862 alot Olean Uneedine ie B.N. Y. & P. pro- 
| file (XVII) 
Ge ae. ee. ss. 864 |Below Olean Crossing by N. Y. & Erie pro-| 
|_ file (X VIII) 
te UP gcentot Se .... | 863 Below Olean—mean of the above levels...) 4578 
This line it will be noted lifts all the levels from Red Bank Junction to 
