LINE A, LONG ISLAND.

--------------+-----------------+-------------------+-------------------------+

| | Station: | Date: |

| |---------+---------+------------+------------+

| | | | | |

Material. | Method. | From | To | From | To |

--------------+-----------------+---------+---------+------------+------------+

All rock |Bottom heading | 69+39.9 | 69+79 |Aug. 2, '06|Sept 25, '06|

| | | | | |

All rock |Center heading | 69+79 | 70+64 |Sept 25, '06|Nov. 21, '06|

| | | | | |

Earth and rock|Center heading | 70+64 | 71+34 |Nov. 21, '06|Dec. 30, '06|

| | | | | |

Earth and rock|Bottom heading | 71+34 | 71+89 |Dec. 30, '06|Feb. 13, '07|

| | | | | |

All rock |Bottom heading | 71+89 | 72+11 |Feb. 13, '07|Feb. 21, '07|

| | | | | |

Earth and rock|Center heading | 72+11 | 72+67 |Feb. 21, '07|Mar. 19, '07|

| | | | | |

All rock |Center heading | 72+67 | 76+54 |Mar. 19, '07|Sept 6, '07|

| | | | | |

Earth and rock|Going out of rock| 76+54 | 77+24 |Sept 6, '07|Oct. 4, '07|

| | | | | |

All earth |Soft ground | 77+24 | 90+57.3 |Oct. 4, '07|Mar. 26, '08|

--------------+-----------------+---------+---------+------------+------------+

--------------+------+--------+--------+--------------------------------------+

| | |Rate of | |

|Number| |progress| |

| of | Linear |in feet | |

Material. | days.| feet. |per day.| Remarks |

--------------+------+--------+--------+--------------------------------------+

All rock | 54 | 39.1 | 0.724 | |

| | | | |

All rock | 57 | 85 | 1.49 | |

| | | | |

Earth and rock| 39 | 70 | 1.79 | |

| | | | |

Earth and rock| 45 | 55 | 1.22 | |

| | | | |

All rock | 8 | 22 | 2.75 | |

| | | | |

Earth and rock| 26 | 56 | 2.15 | |

| | | | |

All rock | 171 | 387 | 2.26 | |

| | | | |

Earth and rock| 28 | 70 | 2.50 | |

| | | | |

All earth | 174 |1,333.3 | 7.66 | |

--------------+------+--------+--------+--------------------------------------+

Transactions of the American Society of Civil Engineers, vol. LXVIII, Sept. 1910 The New York Tunnel Extension of the Pennsylvania Railroad. The East River Tunnels. Paper No. 1159 · 第 19 / 35 题