Class P-1a/b (Locobase 129)

Data from 1930 Locomotive Cyclopedia and from 1927 and 1947 Boston & Maine Description of Locomotives books supplied in May 2005 by Allen Stanley from his extensive collection.

The twelve P-1s were the B & M's first Pacifics.

P-1 3600-3606) was built by Alco in 1910; engine weight was 236,700 lb.

P-1b (3607-3611)

As the specifications suggest, these were typical, not remarkable passenger engines. Bruce Heald, in his Boston & Maine Locomotives (Arcadia Publishing, 2002), p 80, quotes Harry Frye from the latter's Minuteman Steam: "Though faithful performers, they were, for the most part, unexceptional engines and were referred to by some as the Budd cars of the steam era."

(Budd cars were Rail-Diesel Cars (RDC) with diesel engines under the center of the frame that were used for years for local passenger service. Locobase remembers his ride in a Budd car with a leaky exhaust manifold - killer ride, dude!)

After a couple of years, Alco supplied what would be the most numerous B & M Pacific; see Locobase 6630.

Class P-2b/c/d (Locobase 6630)

Data from 1927 and 1947 Boston & Maine Description of Locomotives books supplied in May 2005 by Allen Stanley from his extensive collection.

The P-2 was an enlargement of the P-1 (See Locobase 129). Its boiler had 10 more fire tubes and each tube and flue was a foot longer. When the P-2 was introduced, firebox heating surface included 29.5 sq ft of arch tubes. A later reworking removed one of the arch tubes, but added 62.5 sq ft of thermic syphon. Otherwise, P-2s were essentially identical.

Class P-3a (Locobase 130)

Data from 1927 and 1947 Boston & Maine Description of Locomotives books supplied in May 2005 by Allen Stanley from his extensive collection.

Enlarged P-2s with larger cylinders and 10 tons more adhesion weight, but smaller boilers. 10 built in 1923; retired in 1952-1955.

Class P-4 (Locobase 131)

Data from tables in 1947 Locomotive Cyclopedia. Firebox had 100 sq ft of thermic syphons (3) and arch tubes, Coffin feedwater heaters concealed in the smoke.

The National Park Service's Steamtown collection's Special History Study on the P-4a 3713 notes that it and its sisters were designed to run easily at 70 mph and travel 125 miles on a tenderful of water and 250 miles on coal. The study highlights the starring role these Pacifics played in the B & M's regional passenger service between such cities as Boston and Bangor (Maine), Worcester and Portland (Maine), Springfield (Mass) and White River Junction (Vt), and White River Junction and Troy (NY).

According to the NPS study: When the Boston and Maine took delivery of its second order of Lima Pacifics in 1937 [these would be the last 4-6-2s Lima would build for anybody], it sponsored a contest among New England schoolchildren to name those 10 engines and 10 other passenger engines. The contest was open to any pupil in any community along the railroad and included students from kindergarten to the final year of junior high school. to the locomotive a plate with the name of the boy or girl who suggested the name, as well as the name of his or her school. The contest elicited more than 10,000 names for the 20 engines.

P-4a 3710 Peter Cooper

P-4a 3711 Allagash

P-4a 3712 East Wind

P-4a 3713 The Constitution

P-4a 3714 Greylock

P-4b 3715 Kwasind

P-4b 3716 Rogers' Rangers

P-4b 3717 Old North Bridge

P-4b 3718 Ye Salem Witch

P-4b 3719 Camel's Hump

3710-3714 were P-4a and delivered in 1934; 3715-3719 were P-4b and arrived in 1937.

Described by Drury (1993) as "a quantum leap." Retired in 1953-1954.