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Wednesday, June 29, 2016

Breaching the Stonewall Attack

     I have posted on the Stonewall Attack before: Stonewall and Anti-Stonewall. Also, there is an article on the Stonewall at Chessdotcom that explains the basics. 
     This post contains an interesting game where black played my favorite Anti-Stonewall; he fianchettoed his King's Bishop. I have liked this defense ever since I saw a game many years ago in which Euwe played it. 
     I have Soltis' book The Stonewall Attack and right at the beginning he cautions that white must know the features of the Stonewall so he can adapt his play according to his opponent's plans.  It must be remembered that the Stonewall is NOT a "system" opening where you can play the same moves no matter what black plays. In fact, such openings do not really exist. As in the so called "systems," like the K-Indian Attack, white still has to be flexible in the choice of his opening moves and that means he must put some effort into studying the opening. 
     Soltis also writes that the most difficult setup for white to meet is when black fianchettoes his King's Bishop because it greatly reduces his attacking potential as his B on d3 has little effect. White can try the advance of his f-Pawn, but that also loosens his control of e5. His best procedure is to develop his own dark squared B with b2-b3 and Ba3. White also has the possibility of capturing black's P on c5; white can then use d4 as an outpost for his N. 
    In the following game between a couple of masters it's instructive to see how the moves are dictated by the strategy of both sides. The first idea is black wanting to trade his light squared B and white attempting to prevent it. Black succeeded, but his N on a6 was somewhat out of play and white was then free to commence operations on the K-side even though the absence of his light squared B lessened his chances of success. 
     After black slipped up a bit at move 17 when he loosened the position, play revolved around white trying to open up black's K with f5 and black trying to hinder the P-advance and an exciting struggle ensued. White finally lost his way at move 24 and allowed black to seize the initiative and then missed a tactical shot two moves later and it was all over.

Tuesday, June 28, 2016

Milton Bradley and Chess

Civil War era set
     Milton Bradley (November 8, 1836 – May 30, 1911) was an American business magnate, game pioneer and publisher, credited by many with launching the board game industry in North America with his Milton Bradley Company. 
     Born in Vienna, Maine Bradley grew up in a working-class household in Lowell, Massachusetts after the family moved there in 1847. After completing high school in 1854 he found work as a draftsman and patent agent before enrolling at the Lawrence Scientific School in Cambridge, Massachusetts. He was unable to finish his studies after moving with his family to Hartford, Connecticut, where he could not find gainful employment. 
     In 1856, he left home and got a job in the locomotive works of the Blanchard and Kimball in Springfield, Massachusetts. After the company was closed during the recession of 1858, he entered business for himself as a mechanical draftsman and patent agent. 
     In 1859 Bradley went to Providence, Rhode Island where he spent several weeks learning the craft of lithography then bought a press and started his own business in Springfield. He was initially successful when he sold an image of the little-known Republican presidential nominee Abraham Lincoln. But then a problem arose when, after the print was published, Lincoln took the advice of eleven-year old Grace Bedell, who wrote Lincoln that he “would look a great deal better” if only he would let his beard grow. That meant the prints were worthless and Bradley burned those that remained.  Rather than close up shop, in the winter of 1860 Bradley released a game which he had been working on for some time: The Checkered Game of Life which was based on a game from Europe he had been given; in later years it was named just The Game of Life. One newspaper described the game as being “intended to present to the minds of the young the various vices and virtues with which they will come in contact…and illustrate the effects of each, in a manner that will make a lasting impression."      
The Checkered Game of Life
     The game was an instant success. The players moved using a teetotum. Bradley did not use dice because in those days dice were considered to be wicked and fit only for gamblers. The teetotum determined the advance to squares representing social virtues and vices, such as "influence" or "poverty", with the former earning a player points and the latter retarding his progress. But even the most seemingly secure positions, like "Fat Office", held dangers – "Prison", "Ruin", and "Suicide". The first player to accumulate 100 points won the game.
     During the Civil War many soldiers engaged in off-duty entertainment including poker or dice games while others amused themselves by reading or playing chess or checkers. The source of many of these diversions were games by Milton Bradley. 
     Bradley had intended to volunteer for the Union Army himself, but Captain A. B. Dyer, Superintendent of the Springfield Armory, persuaded Bradley that his talents would be better used as a draftsman at the armory than as a private in the ranks. And so he ended up working nights at the arsenal and during the day printed copies of his new game. 
     Bradley also sold “Games for Soldiers,” a set of nine games that included backgammon, chess, checkers, dominoes, and The Checkered Game of Life. The set was billed in holiday wartime advertisements as “just the thing to send to the boys in camp or hospital for a Christmas present.” The games were packaged in a small box weighing a few ounces and could be sent by mail, postpaid, to any address for just one dollar. 
     The photo below was taken in 1864 just before the Wilderness Campaign and shows then Colonel (later Major General) Martin T. McMahon, assistant adjutant-general of the Army of the Potomac's Sixth Corps, playing the black pieces against another officer.

Monday, June 27, 2016

Theodore Lichtenhein

     Theodore Lichtenhein was a chess master, merchant and Civil War officer who is probably best remembered as one of Morphy's frequent opponents. Born at Königsberg, in East Prussia, on January of 1829, he learned chess at the age of 12 and six years later he was president of the Königsberg Chess Club. He studied for the medical profession prior to entering the service of the Prussian army. During his time in the Prussian Army he abandoned chess until he resumed playing after his arrival in New York. 
     He came to the US in the November 1851 and at first devoted nearly all his time to his mercantile wholesale business. Then in 1856 he joined the New York Chess Club and soon became its strongest member. In 1859 he was the editor of the only weekly newspaper devoted wholly to chess that was published in the United States called The Gambit which lasted on a few months. He also edited a chess column in a German weekly called the New Yorker Humorist und Illustrirte Novellenzeitung and was a frequent contributor to other publications. 
     Lichtenhein, thanks to his safe, careful play captured third place in the 1st American Congress (New York from 6 October – 10 November 1857) which was won by Paul Morphy. Lichtenhein defeated Charles Stanley (3–2) in first round and Frederick Perrin (3–0) in 2nd round before losing to Morphy (0½–3½) in semifinal. He then defeated Benjamin Raphael (3–0) in the 3rd place final. 
     After the tournament he played seven games against Morphy, but succeeded only in drawing three. Two years later when Morphy returned from Europe, the two again met in a match at Knight odds: Morphy won six, Lichtenhein four, and one was drawn. 
     The hostilities of the US Civil War began on April 12, 1861 when Confederate forces fired upon Fort Sumpter and Lichtenhein began serving in the Union Army with the 58th Regiment of New York Volunteers. He also acted as a correspondent for Frank Leslies' Illustrated Newspaper. 
     In those days soldiers were often recruited based on ethnicity or national origin and the local newspaper called for German-speaking men to join the Gallatin (New York) Rifles which was organized by Lichtenhein, who was at the time a local merchant. 
     During the Civil War Lichtenhein saw a lot of action. The Gallatin Rifles joined several other ethnic companies to form the 58th New York Infantry Regiment which fought with distinction throughout the War. The 58th was comprised almost exclusively of men of foreign birth: Poles, Germans, Danes, Italians, Russians and French. Initially there were four separate regiments: 's Gallatin Rifles, Wladimir Krzyzanowski's US Rifles, Julian Allen's Polish Legion, Frederick Gellman's Morgan Rifles and Andrew Lutz' Humboldt Yaegers. 
     On November 7, 1861 the Regiment set off from New York to join the Army of the Potomac. During the first year of the War the 58th New York was encamped in Virginia prior to advancing to Winchester, Virginia in the Spring of 1862 in pursuit of General Stonewall Jackson. 
     On June 2, 1862 the 58th entered its first battle at Cross Keys, Virginia where Krzyzanowski led a successful bayonet charge. After a period of participating in limited engagements, in October of 1862 the Regiment fought in the Second Battle of Bull Run. In 1863 the Regiment fought in the Battle of Chancellorsville after which they began marching towards Gettysburg, Pennsylvania. During the Battle of Gettysburg the 58th defended Cemetery Hill and helped repulse Pickett's Charge. After Gettysburg the outfit shipped out by rail to help relieve the Confederate siege of Chattanooga. In October of 1865 the Regiment completed its service and was mustered out of the Army.
     After the Civil War Lichtenhein moved to Chicago for business reasons and had little time for chess. Unfortunately, shortly after moving to Chicago he became ill with an undisclosed malady and lingered, a hopeless invalid for nearly five years, until the 19th of May, 1874 when he passed peacefully away at the age of 45. According to the Edo Ratings Lichtenhein's rating from 1857 to 1862 was between 2455 and 2490. 

Saturday, June 25, 2016

Shredder Chess

     Three or four computers ago I purchased Shredder Classic 4 so it's long gone, but the other day while looking on a backup CD for another document I discovered the old license code. On a whim I downloaded the Shredder Classic Demo which is a restricted test version you can try free for 30 days; to my surprise the license code activated the program.  To tell the truth, I don't have much use for it and I am not particularly fond of the interface, but it's been fun tinkering with it. 
     On the CCLR 40/40 list Deep Shredder 12 is pretty far down in 26th place with 3029 rating. Shredder 4 Classic dates back to 2009, so by chess engine standards it's pretty long of tooth, but Shredder Classic has the same engine and the same knowledge as Shredder 12 and Deep Shredder 12, but its calculations are not as fast or as efficient. 
     It has four different versions of the engine: Solid, Beancounter, Gambit and Kamikaze. I cannot say exactly how these engines differ because I've never seen an explanation. 
     The program also has what is called a Triple Brain which combines the strengths of two different engines to get the optimum for analyzing. While two engines are analyzing, a third engine will decide which move or analysis is better. In its own search window the Triple Brain will display a value between 0 and 100 percent which indicates how sure about its choice the Triple Brain is. 
     This feature, from what I have read, gives poor results and, really, is not particularly useful. Think about this...in order to decide which move was the best wouldn't the Triple Brain engine have to be stronger than either of the other two? If it wasn't, how would it know which move was better?! 
     For the Triple Brain to work best you should combine two engines with about equal playing strength but different playing styles. I tried a little test after I ran across the a position from a game that was touting the merits of Fritz 15 when it found 31.Nd5 against Black Mamba. Also, what other engines could find it?, I asked. Three minutes was the time limit.

White to move

     Per the instructions I matched up the Beancounter and the Gambit versions and neither found the correct move. Triple Brain selected Beancounter's 31.Ke1, but it wasn't too sure that was the best move, only 6 percent. 
     In the match up between Solid and Kamikaze the Triple Brain went with Kamikaze's move, but it was even less sure about the analysis. Solid did select 31.Nd5 and favored white by 0.45. According to Stockfish the evaluation should be closer to 2.25. 
     How did the "modern" engines do?  On a single core with a 3-minute time limit the following engines passed the test: 

Stockfish 7 (found it instantly) 
Houdini 1.5 (15 seconds) 
Rybka 2.3.2 (20 seconds) 
Gull 3 (25 seconds) 
Fritz 12 (60 seconds) 
Komodo 8 (75 seconds) 
Zappa 1.1 (almost 180 seconds) 

     These engines failed: Crafty 35.Rf7 (0.79) and SmarThink 31.Qc4 (0.87). Giraffe failed miserably thinking black was winning. 31.Ke1 (-2.79). 
     I also tested the Triple Brain in one position from analysis in the previously mentioned Forgacs-Tartakower game in which Stockfish and Komodo differed on their move selections. Triple Brain went with Stockfish, but it wasn't very sure about its choice because after 10 minutes it showed only 5 percent certainty! 
     What's this prove? Shredder Classic 4 sells for 30 Euros ($34.15), but I can see no reason to make the purchase because the engines just aren't that strong. Of course, you can add other engines so basically you are just buying the GUI which, when you think about it, is what you're doing when you buy most other programs because you are going to add Stockfish to whatever engines came with it. Any free GUI and one of the free engines will pack more punch for zero Euros ($0.00), so I do not see Shredder Classic 4 as being such a great value.  I did not test it, but on a couple of forums some posters claimed it was not that great at handling databases.  
     It also shows that if you are doing any analysis you do need to give the engine some time to think. See my post Even Engines Need Time to Think.  Even then in some positions you just cannot be 100 percent sure what the best move is unless you're rated somewhere North of 2400.

Friday, June 24, 2016

Engines and Pawn Chains

     Who's better and by how much? The grandmaster says move A is the best, but a couple of different engine's suggest move B or move C is better. The grandmaster says move A is practically winning, but one engine says the position is equal while the other one says the grandmaster is wrong, his move is slightly inferior. Who do you believe? 
     Analyzing the position in this post taken from Forgacs vs. Tartakower, St. Petersburg, 1914 with different engines reminded me of the classic Abbott and Costello routine Who's On First? 
White to move

      It's clear black is operating on the Q-side while white is conducting operations on the K-side. The K-side attack is of greater importance since the enemy K is facing a potential mating attack and one would expect sacrifices to be necessary at some point. 
     While white's attack seems the more promising, his Pawn chain has all the lines closed so that his pieces cannot participate in the attack.  On the other hand black's P-chain is not weakened in any way, but notice that he has no pieces in the vicinity of his King with which to defend it. Therefore white has to find a way to break through and bring his pieces to bear on the black K. 
     Forgacs' moves 1.f5 and 2.g4 have been universally praised in the books as an example of a brilliant attack. However, analysis with Stockfish and Komodo reveals that Tartakower's defense was rather weak, but had he chosen a better defense the engine's didn't agree on the best continuation. What they did agree on was that white's best line was further preparing the f5 advance by first playing 1.g4. 
     Because some engines are only single core I limited all engines to one core for the comparison test; all detailed analysis was done with engines using three cores.  The engines were given 3 minutes to evaluate the position to see if any of them would discover Forgacs 1.f5 followed by 2.g4 and the subsequent attack on black's King which proved decisive. None did and they all wanted to play 1.g4 except Stockfish and Giraffe.

Engines selecting 1.g4. 
SmarThink (+/-) (0.72) 
Zappa (+/=) (0.63) 
Fritz 12 (+/=) (0.53) 
Komodo 8 (+/=) (0.46) 
Gull 3 (=) (0.39) 
Houdini 1.5 (=) (0.21) 
Rybka 2.3.2 (=) (0.20) 
Crafty (=) (0.02) 
Other first moves: Stockfish 7 1.Qg2 (+/=) (0.56) Giraffe 1.Bb1 (-/+) (-8.22) This is way wrong!

     Using Stockfish 7 and Komodo 8 I looked at the position after Forgacs played 1.f5 and both agreed that 1...exf5 was black's best reply, but after that things got really confusing. Both engines agreed that 2.g4 was best, evaluating the position at almost dead equal. But, after 3.Ng5 they could not agree on either the best more or the evaluation score! At least not in the hour or so I was fooling around with the position. 
     What can we make of this?! Was Forgacs' 1.f5 the best or was it the engine's 1.g4? After I played 1.g4, both engines gave different "best" lines and evaluation cores. I resorted to the old standby that I use in situations like this...a Shootout after both moves.

First with Forgac's 1.f5 Both Stockfish and Komodo 8 scored +0 -1 =4 
Then with 1.g4 Stockfish scored +1 -0 =4 Komodo 8 scored +3 -0 =2 

1) Black has drawing chances after Forgacs' move, but after the engine choice white's winning chances are increased significantly. 
2) In some positions a laptop, a gaggle of engines and a couple of hours analysis is just not enough to determine the BEST lines or even how much better one side stands. 
3) What's practical in over the board play may turn out not to be the "best" according to the engines.

Thursday, June 23, 2016

Engines and Pawn Breaks

     If you analyze with engines you have noticed that various engines don't always agree on the best move. They are all good at spotting tactics, but what if no tactics are available? In endings and even in the middlegame engines sometimes enter positions that are lost because they can overvalue factors like space and material. Larry Kaufman has said engines play at around 2300 or 2400 in these situations; their super-human strength comes from spotting tactics. One area where all the engines seem to struggle is an understanding of P-breaks. 
     Stockfish is good at finding deep tactical moves and for calculating endgames, but it can it can miss some things because of its pruning; it investigates some lines deeply and others not so much. Houdini is pretty good at blitz time controls, but not for deep analysis. Shredder is good in purely positional positions. Komodo is also good for making good positional valuations. It is classical in its approach and is probably the best when it comes to finding P-breaks. 
     What is a Pawn break? According to Dan Heisman, it is a P-move that breaks up the opponent's fixed P-chain by attacking the opponent's Pawns with the Pawn is making the break. C.J.S. Purdy advised that when examining a position you should always look at them because sometimes a P-break can give surprising results. 
     The question we face when making P-breaks is when we should play one. In the following position taken from Panchanathan vs. Novikov, Dallas UTD, 2004, black's P-break 14...g5! was very significant because the key e5 square is what really matters. Black's P-sac gained control of e5 and then white's K was exposed to a dangerous attack. Once the black N landed on e5 square the rest was easy. 
Black to move

     Being curious as to how my engines would play in a situation where a P-break was nearly decisive they were allowed to examine the position for 3 minutes on a single core. Note: Giraffe's evaluation in no way compares to those of other engine's!! For example, after 1.e4 e5 it evaluates the position at +/- and as being 0.87 in white's favor. 
     Of the moves suggested by the engines, six selected the correct move, but their evaluations varied considerably.  Of course, there is always the possibility that had any of the engines not selecting 14...g5 been allowed to think much longer they might have changed their move selection.  That's because all of moves were at least examined by all of the engines and there was not that much difference in the score of their top candidates.

Engines selecting 14...g5
SmarThink - (-/+) (-0.97) 
Komodo 8 - (=/+) (-0.62) 
Stockfish 7 - (=/+) (-0.37) 
Gull - (=/+) (-0.32) 
Houdini 1.5 -  (=/+) (-0.26) 
Shredder Classic 4 Kamikaze  (=) (-0.16) 

Engines selecting 14...Nc5
Rybka 2.3.2 - (=) (0.11) 
Fritz 12 -  (=) (0.03) 

Engine selecting 14...h5
Crafty - (=) (0.12) 

Engines selecting 14...e5
Zappa 1.1 - (=) (0.23) 
Giraffe - (-/+) (-5.62) 

Engines selecting 14...O-O
Shredder Classic 4 Solid - (=) (0.12) 
Shredder Classic 4 Beancounter -  (=) (0.07) 
Shredder Classic 4 Gambit =  (=) (-0.16) 

     Using Komodo how did the other candidate moves fare in engine evaluation? It's evaluations are as follows: 

14...e5 (=) (0.12) 
14...Nc5 (=) (0.01) 
14...h5 (=) (-0.14) 
14...O-O (=) (-0.07) 

     Clearly the strongest engines were up to the task of finding the correct P-break even though they did not agree on the score, but I was rather surprised at SmarThink's evaluation which in this case was probably the closest to what would a human grandmaster's opinion would be even though in engine vs. engine play it does not fare well against Stockfish or Komodo. 
     But, what about a position that involves Pawn chains and a Pawn break? How do the engines handle those positions? I'll look at that in the next post.

Wednesday, June 22, 2016

The Human Giraffe?

     I reasoned that if Giraffe learned from playing itself and games from a database of human games, then perhaps it might play human-like moves. Because at full strength it's supposed to be of IM strength it's obviously too strong for me, but what if I played it using the Fritz Sparring Mode? 
     According to the Fritz documentation, in the Sparring Mode the engine plays a reasonably strong game, but at the same time makes tactical errors. If the program finds a move that allows the opponent to gain a tactical advantage in a clever way, it will play that move. It is a very realistic human style, the kind you encounter in a chess club, or so it says.
     You can select the level of difficulty of the tactics that will be offered. Very easy is for players with an Elo of around 1400 and usually involves finding forks and two move combinations. Normal is meant for players between 1700 and 1900, and very hard is for players from 1900 all the way up to GMs (or so it says). I chose the "very hard" mode with the engine playing fast. 
     I managed to win when Giraffe played rather poor positionally, but it also introduced some tricky tactics. To me, in the Sparring Mode it did play pretty human-like...no playing like a grandmaster, tossing a piece, and then going back to grandmaster-strength play as engines seem to do when they are dumbed down. Conclusion: it might make a good engine to practice against if you are an OTB player and need a partner. 

Tuesday, June 21, 2016

Is the Giraffe Dead?

     Back in September I reported on Giraffe, a deep-learning machine that learned to play chess like humans do. Also, see the article in MIT's Technology Review. 
     The bad news is the project has been discontinued by the author; he explains why on Talk Chess. You can also read an additional article HERE.  The good news is, it is now open source and it will interesting to see if it will ever reach the point where it can challenge the commercial engines like Stockfish and Komodo. 
     Giraffe's CCLR rating is only 2414 placing it way down at 167th place. In obtaining that rating it has not played any of the top engines. One disadvantage Giraffe has it that only uses one core.
     Yesterday I played a match against a version of Giraffe that I download of the CCLR website. It was played at 4-minutes per game using my Expanded Fritz 12 Opening Book and the results were Stockfish scored a decisive +4 -0 =1. 
     Playing over the games I noticed that it played very well then it would make a positional error. On a couple of occasions it seemed like the engine "didn't know what to do" and so made a meaningless King move. And, unlike the leading engines, it committed an occasional tactical error. Also, on more than one occasion, it's evaluation was nowhere near Stockfish's. Maybe this is the result of having learned by "studying" human games!? 
     Thinking that perhaps 4-minute games were not long enough I also did a test game at 10 minutes and it's presented below. Things are pretty even until Giraffe starts making some small positional bad calls in the ending. 
     The claim is that Giraffe taught itself to play at the IM level.  Compared to the super-GM level other engines play at that's pretty good.  But, does it really play at the IM level?  Judging by this game, it looks like it, but not being an IM, I can't say for sure.

Monday, June 20, 2016

Instructive Reshevsky Miniature

     Everybody has their own explanation, but generally speaking, most people consider games of 25 moves or less a miniature. Miniatures are not seen only in the games of non-masters; even world-class players have lost one! 
     What makes them instructive is that they are generally full of tactics. Peter Clarke wrote miniatures are entertainment; they are full of thrills, comedy and farce. Technically the quality of play isn't a criteria, but for the game to have any instructional value it should be free of gross blunders. Clarke noted that when the loser disregards basic principles or makes gross blunders, miniatures have no appeal. Miniatures are the result of mistakes, of course, but they do not arise out of a lack of ability. They are usually the result, he said, of over ambition where the loser tries for too much in the position. 
     The following game does not fit Clarke's definition precisely as the two players, Reshevsky vs. an ordinary master, can't be considered a game in which the players were evenly matched. USCF Master Gallagher didn't lose because of over ambition or trying for too much. He made an elementary mistake, but that's what makes this game instructive...the master made a typical mistake that we all make. 
     C.J.S. Purdy constantly drove home the point in his writings that at EVERY move you have to look around for a SOUND tactic and he gave some helpful advice on how to spot them. See my post Tactics, the Pornography of Chess.  
     Always try to sniff out a tactic if you see: pins or forks, pieces with limited mobility, a piece that could be attacked if a piece that stands between it and a piece of lesser value could be removed (a masked piece), or a piece that is undefended. Always take a gander at Pawn breaks, sacrifices and bizarre moves; something may turn up there. You should also look at what Purdy called "jump checks" which are checks that could be played if a piece could jump over any intervening pieces. 
     In this game Gallagher's mistake was pretty obvious; his 14th move placed a N on a square where it was undefended and Reshevsky immediately took advantage of it. Prior to Gallagher's tactical error though Reshevsky himself made a mistake when he took with the wrong piece at move 14. Reshevsky, who was a fine tactician and excellent at calculating variations, may have seen that 14.Nxd6 was better and believed that he could win the game against a weaker player even if he did find the best defense with 14...Bxb5. But, that's conjecture. After all, Reshevsky was was 79 years old and his rating had slipped to 2459 in 1990 and this was the last US Open (won by Yasser Seirawan) he played in, so he may have just miscalculated. Heck, the year before even I managed to draw a game against him, so he wasn't the Reshevsky of old!

Saturday, June 18, 2016

One of the Best Postal Games in History

     Back in 1980 all of the U.S. correspondence organizations took part in a 50-board match against the Soviet Union. Although the U.S. lost the match the highlight was when, on board one, Tony Cayford defeated the former world correspondence champion Vladimir Zagorovsky. 
     In a poll of Chess Mail players held in 1998 this game was voted as one of the best 20 postal games in history. It may very well be that it is one of the best. 
     I was going to let Stockfish analyze it at 10 seconds a move then go over it and type in a few notes, but the subtitles were tremendous. In the end I spent half a day looking at the game! 
     Were engines used in this game? In 1945 Alan Turing (1912-1954) used chess-playing as an example of what a computer could do and in he wrote the first computer chess program.
     By 1956 experiments were being run on a Univac MANIAC I computer which performed an astonishing 11,000 operations a second and used a 6x6 chessboard without Bishops to play chess. It required 12 minutes to search to a depth of 8 plies. Chess programs were making rapid progress because the following year a chess program at MIT could do 42,000 operations per second and had a memory of 70K with a 4-ply search taking 8 minutes. By 1963 Botvinnik was predicting that a Russian chess playing program would eventually defeat the World Champion. 
     Chess computers didn't enter the real world of chess until 1966 when a computer from MIT was entered in the Massachusetts Amateur championship where it scored +0 -4 =1 and obtained a USCF rating of 1243. The following year the computer actually beat its first human (who was rated 1510) and it finished the year with a record of +3 -12 =3. By then the idea of chess computers was becoming a real topic of discussion and in 1968 IM David Levy made his famous $3,000 bet that no chess computer would beat him in 10 years. He won the bet. 
     It wasn't until the early 1970s that engines actually began showing real promise and in 1975 David Bronstein used the endgame database in KAISSA to win an adjourned game in a tournament in Vilnius. And, in 1976 a program named CHESS 4.45 won the Class B section of the Paul Masson tournament in Northern California with a performance rating was 1950.
     In 1977 CHESS 4.5 won the Minnesota Open with a score of +5 -0 =1 and its performance rating was 2271. That was the year Michael Stean went down in history as the first grandmaster to lose to a computer even if it was it only a blitz game. In 1978 SARGON won the first tournament for microcomputers, David Levy won his 10 year bet by defeating CHESS 4.7 and experts predicted that a computer would be world chess champion in 10 years; they were wrong. 
     By the early to mid-1980s that engines actually began to become a serious threat to humans. But, for the general public in 1980, when this game was played, not much was available. In 1979 Novag had come out with its dedicated Chess Champion Mk II and in 1980 there was a chess program for the Tandy Radio Shack Color Computer that I owned that ran off a cassette tape. The manual for this program is available online HERE.  It's funny now, but the color selection gave two options. Orange and pink pieces on a turquoise and light grey board or red and blue pieces on a green and yellow board. I said all that to say this: chess engines were no help to the players at the time this game was played. 

The players: 
Richard Anthony (Tony) Cayford was born on December 3, 1939 and lived in Manchester, New Jersey. He was originally from Canada but moved to the U.S. in the mid-1960s.  His correspondence record was impressive: 
1962-Canadian CC Open Champion 
1964- second in the Canadian CC Open 
1972-Golden Knights champion 
1973-tied for first in the Golden Knights 
1974-75-winner of the First US CC Championship 
1992-winner of the First Anglo-Pacific Tournament 

     He was awarded the Senior IM Correspondence title in 2000 and his ICCF rating was 2492 Cayford was once active in OTB play and in 1961 he tied for third in the Canadian Closed Championship and after some success in tournament on the East Coast after moving to the U.S., but increasing commitments to business and his family he decided to switch exclusively to correspondence play for the CCLA and Chess Review. Under the Chess Review postal rating system that was in effect his rating was second only to that of Hans Berliner and at one stage he had a streak of 77 straight wins.  Cayford died September 22, 2005. 

Vladimir Pavlovich Zagorovsky (June 29, 1925 in Voronezh, Russia, formerly USSR – November 6, 1994) was a Russian grandmaster of correspondence chess. He is most famous for being the fourth ICCF World Champion between 1962 and 1965. OTB he won the 1952 Moscow City Championship.  On the July 1972 FIDE rating list he had an over the board rating of 2370.