INTRODUCTION TO MY BOOK "The Surveying of the Hoosac Tunnel and Troy & Greenfield Railroad

INTRODUCTION

The Hoosac Tunnel is a four and three quarter mile long railroad tunnel which bores through the Hoosic Mountain range in the northwestern corner of Massachusetts. It was built between 1851 and 1875. It was, and still is, one of the finest examples of precision surveying in the world. During the same time period, the Troy and Greenfield Railroad was constructed from Greenfield, Massachusetts to the Massachusetts/Vermont Border at Williamstown, Massachusetts and Pownal, Vermont. It was approximately 42 miles long, and was constructed as part of a plan to construct a railroad from Boston, Massachusetts through the Hoosac Tunnel to Troy, New York and points west.

The Hoosic Mountains in northwestern Massachusetts are a small mountain range which shed their water towards the Connecticut River on their East and toward the Hoosic and Housatonic Rivers on their West. Its mountains are considered part of the Berkshire Mountain range in western Massachusetts and the Green Mountain Range in southern Vermont. Its highest peak is Crum Hill in Monroe, Massachusetts at an elevation of 2841 feet above sea level.

It should be noted that the spelling differences in Hoosic Mountains, Hoosic River, Housatonic River, and Hoosac Tunnel all stem from various interpretations of the Indian words used in the region. The spelling differences have been carried on to modern times. This paper has tried to be consistent but seeks no argument with those that differ about the spelling.

The Tunnel's eastern portal is in the Town of Florida, Massachusetts near the most westerly reach of the Deerfield River. At that point, its track bed is 779 feet above sea level.

Its western portal is in the Town of North Adams, Massachusett near the most easterly reach of the South Branch of the Hoosic River and is 10 miles from the New York/Massachusetts/Vermont corner stone. Its track bed at the western portal is 777 feet above sea level.

At its deepest point, the tunnel is 1718 feet below the ground surface of the Hoosic Mountains.

Its central shaft is a 1028 foot deep perpendicular shaft above the high point of the track bed, which is 828 feet above sea level.

When the bores met from the east and west portals on November 27, 1873, the greatest deviation from the intended alignment was 9/16 of an inch (0.047 feet). When considering the length of the two bores, this deviation would be a ratio of 0.047 to 12,837, or one part in 273,710! To the best of my knowledge, that surveying measurement accuracy has never been duplicated in hard rock bores to this day, 145 years later!

A common myth in the area is that Mount Greylock, the highest peak in Massachusetts at 3489 feet above sea level, is part of the Berkshire Mountain Range. Mt. Greylock is actually part of the Taconic Range, and is adjacent to the western flank of the Hoosic Mountains, with the South Branch of the Hoosic River flowing between them. The valley between the two mountain ranges made it possible to sight the West portal from the summit of Mount Greylock. At the time of the construction of the tunnel, much of the land in the area was cleared farmland. The opening at the west portal four and three quarters miles away was visible 2712 feet below the top of Mt. Greylock.

By the time the preliminary surveys for the Hoosac Tunnel alignment were done in 1851, the methods, tools and instrumentation being used were very far advanced. In addition, the Tunnel layout and construction demanded the development of methods and instruments never used before.

The Tunnel is famous for construction “firsts,” such as the use of nitroglycerine and power rock drills.

The surveying for the Tunnel is also the story of many “firsts,” not only in Massachusetts, but also in the United States. Many of the surveys were not done in anticipation of the Tunnel, but, coincidentally, served as excellent surveys for the Tunnel route studies, design, and layout. The accuracies of the horizontal and vertical alignment of the Tunnel would not have been possible without the efforts of one man named Simeon Borden, whose surveying work was done more than 30 years before the Tunnel was constructed.

Simeon Borden

In New England between 1831 and 1836, Simeon Borden performed one of the most significant, and first-of-its kind, surveys done in the world. It was the Trigonometrical Survey of the State of Massachusetts. The survey was done for the express purpose of defining and mapping political boundaries (town, city, county and state), and determining accurate elevations of peaks within and near the boundaries of the Commonwealth. Today, it is more correctly named a “Geodetic Survey” because it considered the shape of the earth when all of its surveying data was gathered and calculated.

The desired end result of a surveyor's work has never changed between then and now. It is to to determine the latitude, longitude and elevation of specific points, today usually expressed as the X, Y, and Z co-ordinates of a point, or co-ordinated geometry. The surveyor then shows these points in graphic form on a map or plan. What has changed since the BC era are the methods, tools, and instrumentation used to determine and map the X,Y, and Z coordinates of points.

Quite often, the term “The Men and their Machines” is applied to major engineering works. In my opinion, the expression, “The Men and Their Knowledge” is much more applicable to the building of this Tunnel.

First Railroads

The first railroads in America were conceived and built for commercial purposes: for the movement of goods and to transport passengers from one place to another. Railroads soon developed into the most reliable, efficient, and quickest method of transportion within the continental United States. As such, the growth of the railroad industry was a major contributor to the rapid economic progress of the United States in the last half of the 19th century.

Granite Railway

Most railroad historians consider the first railroad built in the United States to be the Granite Railway in Quincy and East Milton, Massachusetts. It was chartered by the Massachusetts Legislature on April 1, 1826, and began operation on October 7th of the same year. It was three miles long and was built to carry stone from a quarry in Quincy to a dock on the Neponset River in East Milton. The stone was then transported by boat to Charlestown and used to build the Bunker Hill Monument.

The engineer for the Granite Railway was Gridley Bryant (1789-1867). He found it necessary to design and build many features that were later used by most railroads. They included switches, double-wheel trucks, load transfer equipment, and turntables. He never patented any of his inventions, but somehow he was able to keep others from claiming they were the first inventors of these designs.

The grades of the tracks were so well laid out by surveyors that a single horse could pull three cars loaded with 16 tons of granite blocks for the railway's three-mile length.

Mohawk & Hudson Railroad

The 16-mile long Mohawk & Hudson Railroad from the Hudson River in Albany, New York to the Mohawk River in Schenectady, New York was the second commercial railroad built in the United States.It was incorporated on April 9, 1826 and began operation on August 9, 1831. It was built with the intention of by-passing the Erie Canal and cutting the transportation time from Albany to Schnectady from one day to one hour. It eventually became part of the New York Central Railroad System.

THE DEWITT CLINTON TRAIN ON THE MOHAWK & HUDSON RR – 1831

The irony is that these two railroads, the Granite and the Mohawk and Hudson Railway, were connected when the Hoosac Tunnel in Western Massachusetts began being used on April 5, 1875. That connection would never had been made without the work of surveyors. Long before the connection was made, surveyors were gathering information about the land which the railroad would eventually traverse. This information was invaluable to the engineers who studied the land to determine where the railroad routes should be located and then to design the railway's path.

Railroad design made rapid improvements between 1826 and 1875.

Hoosac Tunnel

Prior to the Hoosac Tunnel being built, nine railroad tunnels had been built in the United States.

The 901-foot long Staple Bend Tunnel in the town of Mineral Point, Pennsylvania was the first railroad tunnel in America. It was built in 1833. It was built through solid rock.

The longest tunnel was the 4273 feet (0.81 miles) long “Blue Ridge Tunnel” completed in central Virginia in 1858. Several of these tunnels were of the “cut and cover” style, which means a trench was dug in the ground on the intended route of the railroad, the tracks were laid, and then a “roof” was built over the trench. Several others were built by drilling into hard rock with hand drills and then blasting the rock with black powder; nitroglycerine was not available in America. None of the tunnels was considered long enough to need a vertical shaft from the surface over the tunnel down to the tunnel. All of them, however, could not have been built without the help of surveyors.

Carved through the Berkshire Mountains, the 25,301 foot long Hoosac Tunnel demanded a need for improvements in surveying methods, engineering design, equipment, and construction. Men had to drill and blast the entire length of the tunnel, 4.79 miles, through hard rock. Hand drills and black powder were slow and dangerous.

The inventions of machine-powered rock drills and nitro-glycerine to shatter the solid rock increased the ability of the workmen to remove rock many times over. The use of machine drills and nitro-glycerine took place during the Tunnel's construction and made it a proving ground for these important mining tools.

Less well known, but equally important, was the Tunnel's need for the refinement of previous surveying methods to accommodate its design and layout.

To the layman, railroads are designed and built by civil engineers. The engineer, however, could neither design nor build a railroad without the accurate existing conditions surveys and construction layout surveys. Construction layout surveys required high accuracy in both the horizontal and vertical planes which are commonly referred to by surveyors as “line and grade.”

The need for the more accurate and refined surveys made railroad surveyors some of the best in the surveying profession. It was during the Hoosac Tunnel era that they achieved this status. The surveys for the tunnel and the rail lines through it were the first of their kind in North America, and one of several surveying “firsts” which took place in Massachusetts.

These chapters tell of surveys done long before the Tunnel was conceived and how they became the basis of the design and layout for its construction. It tells how these earlier surveys became an integral part of the surveying for the Hoosac Tunnel.

This story of surveyors, using their knowledge and skills to solve a highly technical construction problem, has never been told before. To understand the complexity of the problem and how the surveyors were able to acquire almost unbelievable accuracies in constructing the Tunnel, the history of surveying methods and instruments needs to be understood. It begins more than 4000 years before the Hoosac Tunnel was built, and becomes a wonderful part of American history.

I have enjoyed retelling this story.