Class Attelborough (Locobase 9540)

Data from table entitled "Motive Power Boston & Providence Railroad Company," Railway and Locomotive Engineering, October 1899, page 443, which was prepared by George S Griggs, then (November 1856) Superintendent of Motive Power at the B & P's Roxbury, Mass Machine Shop. NB: Boiler pressure is an estimate.

The last of the engines on George Griggs' 1856 list was this smaller Eight-wheeler that may have been built as a replacement for an earlier locomotive.

Class Bristol (Locobase 9526)

Data from table entitled "Motive Power Boston & Providence Railroad Company," Railway and Locomotive Engineering, October 1899, page 443, which was prepared by George S Griggs, then (November 1856) Superintendent of Motive Power at the B & P's Roxbury, Mass Machine Shop. NB: Boiler pressure is an estimate.

Griggs' third Roxbury-built machine was delivered a month after Suffolk in June 1846 and combined the larger boiler of the second engine with the shallower firebox.

Class Iron Horse (Locobase 9531)

Data from table entitled "Motive Power Boston & Providence Railroad Company," Railway and Locomotive Engineering, October 1899, page 443, which was prepared by George S Griggs, then (November 1856) Superintendent of Motive Power at the B & P's Roxbury, Mass Machine Shop. NB: Boiler pressure is an estimate.

Griggs clearly was designing different engines for specific service. This next Roxbury engine, delivered in September 1848, reverted to a smaller grate and cylinder volume, but lengthened its boiler by a foot. Rhode Island (Locobase 9532) was identical except for cylinder volume and driver diameter.

Class Mansfield (Locobase 9539)

Data from table entitled "Motive Power Boston & Providence Railroad Company," Railway and Locomotive Engineering, October 1899, page 443, which was prepared by George S Griggs, then (November 1856) Superintendent of Motive Power at the B & P's Roxbury, Mass Machine Shop. NB: Boiler pressure is an estimate.

Another of the very few foreigners on Griggs' 1856 list, this Massachusetts engine was quite a bit bigger than any of the homebuilts (and most Taunton locomotives of the time) and showed very many of the characteristics typical of an American Eight-wheeler of the time.

Class Narraganset (Locobase 9530)

Data from table entitled "Motive Power Boston & Providence Railroad Company," Railway and Locomotive Engineering, October 1899, page 443, which was prepared by George S Griggs, then (November 1856) Superintendent of Motive Power at the B & P's Roxbury, Mass Machine Shop. NB: Boiler pressure is an estimate.

Virtually identical to the Taghconic that had appeared a month earlier, the Narraganset was the most powerful Griggs engine so far. Its larger cylinder volume raised the yet-to-be-calculated tractive effort.

Class Neponset (Locobase 9535)

Data from table entitled "Motive Power Boston & Providence Railroad Company," Railway and Locomotive Engineering, October 1899, page 443, which was prepared by George S Griggs, then (November 1856) Superintendent of Motive Power at the B & P's Roxbury, Mass Machine Shop. NB: Boiler pressure is an estimate.

This was the only Griggs engine that would have the 2"-diameter boiler tube that would be a standard size later on in the Century. Its delivery in June 1849 provided a passenger engine with a slightly larger boiler.

Class Norfolk (Locobase 9524)

Data from table entitled "Motive Power Boston & Providence Railroad Company," Railway and Locomotive Engineering, October 1899, page 443, which was prepared by George S Griggs, then (November 1856) Superintendent of Motive Power at the B & P's Roxbury, Mass Machine Shop. NB: Boiler pressure is an estimate.

George Griggs' first home-built locomotives set the pattern for the next several B & P engines. Norfolk, Suffolk (Locobase 9525), and Bristol (Locobase 9526) were virtually identical but are shown to illustrate the tentative nature of Griggs' first efforts. Norfolk was completed first in May 1845 and had the smallest drivers and the fewest tubes.

Class Providence (Locobase 9533)

Data from table entitled "Motive Power Boston & Providence Railroad Company," Railway and Locomotive Engineering, October 1899, page 443, which was prepared by George S Griggs, then (November 1856) Superintendent of Motive Power at the B & P's Roxbury, Mass Machine Shop. NB: Boiler pressure is an estimate.

One of the few "foreign" engines to appear on Griggs' 1856 motive power was this slightly smaller locomotive from another Massachusetts builder delivered in February 1849. Its firebox was a bit bigger in relation to its tube surface area, but the other dimensions were not significantly different.

Class Rhode Island (Locobase 9532)

Data from table entitled "Motive Power Boston & Providence Railroad Company," Railway and Locomotive Engineering, October 1899, page 443, which was prepared by George S Griggs, then (November 1856) Superintendent of Motive Power at the B & P's Roxbury, Mass Machine Shop. NB: Boiler pressure is an estimate.

Rhode Island shared virtually all of the major dimensions with Iron Horse, which also entered service in Septermber 1848. Its stroke was 2" longer and it stood on taller drivers, suggesting a more resolutely passenger-service orientation.

Class Suffolk (Locobase 9525)

Data from table entitled "Motive Power Boston & Providence Railroad Company," Railway and Locomotive Engineering, October 1899, page 443, which was prepared by George S Griggs, then (November 1856) Superintendent of Motive Power at the B & P's Roxbury, Mass Machine Shop. NB: Boiler pressure is an estimate.

Griggs' second B & P machine added a few tubes to the boiler and deepened the firebox, but was otherwise similar to the Norfolk although it was delivered a year later in May 1846.

Class Taghconic (Locobase 9529)

Data from table entitled "Motive Power Boston & Providence Railroad Company," Railway and Locomotive Engineering, October 1899, page 443, which was prepared by George S Griggs, then (November 1856) Superintendent of Motive Power at the B & P's Roxbury, Mass Machine Shop. NB: Boiler pressure is an estimate.

The Eight-wheeler design was beginning to take its most recognized form, but it was still small.. Grate area still came in below 10 sq ft and the total heating surface was less than 700 sq ft. Output at the B & P's Roxbury shop was about to jump with this first of the 1848 locomotives.

Class Washington (Locobase 9538)

Data from table entitled "Motive Power Boston & Providence Railroad Company," Railway and Locomotive Engineering, October 1899, page 443, which was prepared by George S Griggs, then (November 1856) Superintendent of Motive Power at the B & P's Roxbury, Mass Machine Shop. NB: Boiler pressure is an estimate.

September 1854 was only 2 years before Griggs published the table from which the Locobase entries have been taken. By this time, he had adopted the standard Eight-wheeler layout, although the dimensions were still a bit small. New York, which followed in December 1854 may have been an identical design except for the smaller drivers (60") and tubes that measured 2 ft longer.

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