In 1886 and 1887 the Chess Journal held a series of monthly
pleisoi was used to specify problems
with multiple solutions.
Several terms for this type of problem were tried out: pleistoi
problems, plurima problems, polypragmon problems and
multiplex problem, but pleisoi was the term that survived
the longest in the Chess Journal. (Later use includes A. White: Tasks and Echoes (1915), p. 217, prb. 100B, but as that problem is taken from
Chess Journal, Feb. 1887, prb. 1695 it is not independent use. No later use has
been identified so far, so the term does not appear to have made it into general use.)
Initially, requirements were for direct mates in orthodox settings and with dual-free solutions, but over the first two or three months, different classes of pleisoi records developed (see v. 10, i. 91 (Oct., 1886), p.32, 33, 34):
Class I: no obtrusive pieces, no duals after key move.
Class II: no obtrusive pieces, duals after key move allowed.
Class III: with obtrusive pieces, no duals after key move.
Class IV: with obtrusive pieces, duals after key move allowed.
An expressed intention was to find maximum problems, which makes these tourneys as a whole an early form of task-record tourneys.
The first tourney (August, 1886) was run more or less as a normal tourney: it required problems with multiple mates in #1, #2 and #3, and the #1 problems should exceed 47 mates. Two of the prizes were awarded, but the #3-prize has not been identified.
A special prize was awarded to a problem from England that had not arrived in time for the closing date. However, as the tourney was for Class I pleisoi (not explicitly, but implicitly as classes had not been defined at the time), only the 24 key-moves were counted. It was later described as a class II pleisoi: duals should probably be considered in the total number of solutions.
The second tourney (September, 1886) required pleisoi problems in #1 and #2 moves, but there was no express requirement to exceed the number of mates from tourney 1.
In October (p. 30), four prizes were offered for the best pleisoi in each class in two moves, "our object being to reach the maximum and then go for something else". From this date prizes were awarded as monthly prizes, as shown below, occasionally extended with special prizes. The first group of awards included a #3 problem—this might be from tourney 1, although no such connection is stated.
From November, no further prize pleisoi announcements are made, although prizes continue to be awarded.
The full list of prizes (ordinary as well as special) is as follows:
|Sep., 1886||1556||I||#1||40||I/#1 maximum|
|Oct., 1886||1597||III||#1||94||III/#1 maximum|
|June, 1887||1755||I||#2||107||I/#2 maximum|
|July, 1887||1798||III||#2||193||III/#2 maximum|
The number of keymoves/solutions are as given in the solutions to the problems.
The maximum pleisoi of each class and nr of keys/solutions are given on diagrams below.
In 1873 (or possibly late 1872), the editor of Chess Journal (Orestes Augustus Brownson, Jr.) published a book or pamphlet titled Chess Plurima. Problems, Games, Anecdotes &c., but this particular use of the term plurima seems to be unrelated. (The book is not in Betts, but appears in the Cleveland Public Library catalog. The title page and p. 1–12 also appear to have been included with Chess Journal, v. 5, i. 35 (Jan., 1873).)
Source: Chess Journal, i. 91 (Sep., 1886 ) p. 14, prb. 1556
Source: Chess Journal, i. 98 (Apr., 1887 ) p. 25, prb. 1756
Count: 94 [?]
Source: Chess Journal, i. 92 (Oct., 1886 ) p. 30, prb. 1597