Last update April 6, 2013
It's not uncommon to occasionally stumble across various mistakes and typos as you read a Three Investigators book. Incorrectly spelled words are easy to spot as are illustrations that don't match what is described in the text.  But some mistakes, like continuity errors and inconsistencies in the stories, are difficult to catch unless one is really paying attention. For example, there are only thirteen plaster busts in "The Mystery of the Fiery Eye" but the attentive reader may note that the author gives them fourteen different names and even loses track of which ones have been sold!  Unlike the publishers of many juvenile series books, Random House made every effort to correct errors when they were brought to their attention. Thus, it is more common to find errors in the earliest editions of a given title and even more so in the earliest printings.  

With this page we're going to attempt to document all of the known errors and to also identify when and where the error was corrected (if it was).  This information can be useful in helping to determine in better detail the printing history of a title and it can also contribute to our overall knowledge of this series.  We need your help!  Let us know when you spot an error of any sort and, if you wish, we'll be happy to credit you with the discovery.  But, please keep in mind, this does not necessarily mean that you were "the first" person to ever discover this error.  This is particularly true if the error was fixed in a later
edition or printing.
On the rear cover of any Random House hardcover trade edition which lists either four or six titles, "The Secret of Terror Castle" is incorrectly titled "The Mystery of Terror Castle".  
[First mentioned by Mark Zahn around 2000 on The Jones Salvage Yard Forum.]

#1 The Secret of Terror Castle

Text Error:  In true First Printings of both the hardback trade and GLB editions two lines of text on page 47, lines 16 and 17,
                 have been transposed.  

                 HISTORY: This error was caught by Robert Arthur and mentioned to Walter Retan in a letter dated Oct. 18,
                 1964.  In a Random House memo to Ada Vine dated Oct. 19, 1964, Walter Retan asks that the error be
                 corrected in the next printing.  
                 [Modern readers were not aware of this error and its correction until recently. In 2003, "thrasherperf" posted his
                 discovery of the error at The Jones Salvage Yard forum, post #390.  Unbelievably, it took four years for Seth
                 Smolinske to track down and discover in March, 2007 (aided by a helpful comment made by Philip Fulmer) that
                 this error was corrected in the Second Printing. 

Typo:  The ninth paragraph of chapter four reads: "They were still climbing up a narrow, winding road. without a house in
          sight anywhere."  Of course, there should be no period between the words "road" and "without". 
          [Thanks to Chris Workman for catching this error on Dec. 21, 2011.]
          This error exists in the original Random House hardback edition and the Marchesi paperback and the Hitchcock
          paperback edition.  It was finally corrected by Random House in the 1985 revised Keyhole paperback edition.  
          Curiously, the typo was corrected for the Scholastic edition in 1971 and for the Windward edition in 1972. -STS

Continuity Error:  In the chapter "Interview with a Ghost", Pete asks Stephen Terrill about the eye that looked at them from
                          the painting that first night.  Terrill explains that it was his eye looking at them from a hole in the painting
                          and that he hung a similar painting in its place, after they fled, just in case they came back to look at it.
                          But, back in chapter five, Jupiter and Pete clearly examine the painting with flashlights and determine 
                          that it's definitely a painted eye and not real, before they fled the castle.
                          [Thanks to E. Scott Hood for sharing this in post #390.8 of The Jones Salvage Yard Forum.]

Text/Illustration Error:  On page 75 of the hardbound trade edition the text states that the man holds the machete in his left
                                 hand but the illustration shows it in his right hand.  
                                 HISTORY: In a Random House memo dated Aug. 30, 1972, Jenny Frisse (Fanelli) asks Ada Vine to
                                 correct this error for the hardback and Windward editions.

#2 The Mystery of the Stuttering Parrot

Cover Art "Error":  Over the years, many folks have commented on what appears to be a huge error on the original hardback
                           and the Windward paperback covers which show T3I inside headquarters with a colorful parrot instead of
                           Blackbeard the mynah bird. There is no such scene in the book with a parrot but then there are many T3I
                           covers which exaggerate to some degree or even completely mislead a reader about the contents of a
                           book.  This example was probably a deliberate error on the part of the artist (Ed Vebell created both of
                           these covers) and the editors who wanted to incorporate a colorful parrot from the title into the artwork to
                           make a more eye-catching cover.  However, text on page 59 clearly indicates that all seven parrots had
                           "yellow" heads.  The parrot on the original hardcover book shows a parrot with a red head but this error
                            was corrected by Vebell for the Windward paperback which shows a yellow-headed parrot.
                            [Thanks to both Chris Workman and Derrel Greer for simultaneously pointing this out the week of 
                             Dec. 18, 2011.]

Title Page Errors:  In true First Printings of both the hardback trade and GLB editions there is no mention of the author, and
                           Ed Vebell is incorrectly credited as the illustrator (though he did paint the cover).  
                           HISTORY:  In a letter to Walter Retan dated April 17, 1964 which mostly discusses "Terror Castle",
                           Robert Arthur writes, "Please request that nothing be done in the way of paging and plating the title page
                           and the reverse of it until we can hear from Lee Wright.  I have asked her to investigate the possibility of
                           putting my name on the title page at least on an equal footing with the illustrator . . ."

                           In a letter to Walter Retan dated Oct. 18, 1964 Robert Arthur writes: "Thank you for the copies of 
                           STUTTERING PARROT.  They look very nice with my name in them."
                           [There is no question in my mind that these copies were First Printings that had the original title pages
                           razored out and replaced with the professionally tipped-in corrected title page as described in my
                           "T3I Guide" - STS]

Typo:  In true First Printings of both the hardback trade and GLB editions, third line from the bottom, the word "get" should
          be "pet".  Robert Arthur also mentions this error in his Oct. 18th letter to Mr. Retan and the error is corrected in true
          Second Printings but, of course, it is NOT corrected in copies of the First Printing where the incorrect title page was
          razored out and replaced with a professionally tipped-in corrected title page.

Illustration Errors:  On page 107 of the hardback trade and GLB editions, and the Windward and Marchesi paperback trade
                            editions, Harry Kane's illustration clearly depicts Jupiter and Pete sitting on the couch instead of Bob
                            and Pete as described in the accompanying text.  
                            [Thanks to Philip Fulmer for first mentioning this on his site circa 2000.]

                            A similar error occurs in Kane's illustration on page 129 of these same hardback and paperback editions
                            where Jupiter and Pete are shown sitting in the van but it should be Bob and Pete.  For additional
                            interesting information on the original sketches and their comparison to the final published illustrations 
                            in this book, please visit this page of the site: Stuttering Parrot Sketch/Illustration Comparison Page.

#3 The Mystery of the Whispering Mummy

Typos:  The following two typos can be found in the hardback trade edition and the Marchesi and Hitchcock paperback
            edition (thanks to Chris Workman for pointing these out on Dec. 26, 2011):
            - Page 23, 7th full paragraph, the first sentence reads: "Yes, Wilkins." Professor Yarborough replied. There should
              be a comma, not a period, between "Wilkins" and "Professor."
            - Page 155, last paragraph, the sentence reads: "They, lifted the lid and peered in." There should not be a comma
              between "They" and "lifted."
            [Both of the above typos were corrected for the Scholastic, Keyhole and Dodge paperback editions along with the
            Weekly Reader hardback edition. - STS]

#4 The Mystery of the Green Ghost

Typo:  In the hardback trade edition and large Scholastic pb edition, page 36, line 11, the word "Verdant" is incorrectly
          spelled "Verdent".  This error was corrected in all later paperback editions.
          [Thanks to Garth for mentioning this in post #36.88 of the Jones Salvage Yard Forum.]

Text Error:  In the hardback trade edition, page 85, Bob's horse should be called "Rockingchair" not "Rockinghorse".

Text Error:  In the hardback trade edition, page 89, four lines up from the bottom, "Pete and Chang" should read "Bob and

                 HISTORY:  In a Random House memo dated Dec. 6, 1967, Jean (Van Leeuwen) requests that Ada (Vine) make
                 the corrections for both of the above-mentioned text errrors in future printings. 
                 [Hardback trade editions with ten and more titles listed on the rear cover should contain these corrections.]

Text Error: In the hardback trade and the large-sized Scholastic paperback editions, page 96, seven lines up from the
                bottom, "Bob and Chang" should read "Pete and Chang".
                [Thanks to Telle Tully and his son for reporting this error on Aug. 29, 2011.]
                Curiously, this error was only corrected in the small-sized 1980's Scholastic paperback edition (page 97) with
                Charles Liese cover art but can be found in all other U.S. hardback and paperback editions (the error is found
                on page 95 of the 1979 Hitchcock, the 1985 Keyhole and the 1998 Dodge paperback editions). -STS

#5 Vanishing Treasure

Text Error: In the hardback trade edition, page 89, final line of text, "Bob and Pete" should read "Jupiter and Pete".
                This error was never corrected and appears in the final line of text on page 85 of the Hitchcock, Keyhole and
                Dodge paperback editions.

#7 The Mystery of the Fiery Eye

Story Inconsistency:  On page 4 of the hardback trade edition we learn that Uncle Titus has purchased the following
                                thirteen plaster busts: Julius Caesar, Octavian, Homer, Dante, Francis Bacon, Shakespeare,
                                Augustus of Poland, Luther, Bismarck, Queen Victoria, Washington, Franklin (Ben), and Lincoln.

                                On page 45 we learn that eight of the busts have been sold and the following five remain at the                                            Salvage Yard: Washington, Franklin, Lincoln, Francis Bacon and Theodore Roosevelt (where did
                                Teddy come from?!).

                                On page 75 a lady wants to return two busts that she purchased, they are: Augustus of Poland and                                    Francis Bacon (one of the five busts listed on page 45 that hadn't sold!).
                                [First posted at The Jones Salvage Yard Forum on Jan. 8, 2003 by Seth Smolinske.]

Text/Illustration Error:  On page 54 of the hardback trade edition Three-Dots arrives at the salvage yard in a sleek sedan
                                 "driven by a man in a chauffeur's uniform".  There is no mention of the chauffeur leaving the car which
                                  is clearly empty in the accompanying Kane illustration.
                                  [Thanks to Derrel Greer for catching this error on Aug. 14, 2011.]

Illustration Error:  The art on page 113 of both the hardback trade edition and the Marchesi paperback edition shows Jupiter,
                          Pete, and Bob in the cellar of August's home. This should be Jupiter, Pete, and Gus, as Bob is not with
                          his fellow Investigators when they explore the mansion.
                          [Thanks to Chris Workman for pointing out this error on Jan. 3, 2012.]

Trivia:  From the text, this story takes place from Friday, August third (Jupiter meets Mr. Gelbert about the Rolls) through               Monday, August sixth (when the ruby is found). However, in 1967 (when "Fiery Eye" was written), August third was
          a Thursday and the sixth was a Sunday. The closest years where the third is a Friday and the sixth is a monday
          are 1962 and 1973.  [Thanks to Samuel Kelly for sharing this on Jan. 13, 2013.]

#8 The Mystery of the Silver Spider

Text Error:  On page 131 of the hardback trade edition the first line reads "Two guards escorted Pete, Bob and Rudy 
                 back . . ." but it should read "Two guards escorted Jupiter, Bob and Rudy back . . ."  

                 HISTORY:  In a Random House memo dated 2/27/68, Jean Van Leeuwen asks Ada Vine to make the correction
                 in the next printing of this title. 
                 [Copies listing up to ten titles on the rear cover all seem to contain the error.  Copies with twelve and more titles
                 on the rear cover all seem to contain the correction.  It is possible that some copies listing ten titles on the rear
                 cover may contain the correction and it is possible that some copies listing twelve titles on the rear cover may
                 contain the error, please let us know if you encounter such a copy. -STS]

#9 The Mystery of the Screaming Clock

Cover Art:  Harry Kane made an error on the clock dial found on the front cover which almost wasn't caught by the editors.
                But it was discovered at the very last minute and Harry Kane was able to correct it.  Look closely at the Roman
                numerals "II" and, particularly, the "III" in Pete's shadow and you'll see that they are a little rough in appearance,
                not quite the same size as the other numbers.  This is most likely where the error was made and corrected.
                [As mentioned HERE, the word "RUSH!" is found on the matte to this painting, now we know why! -STS]

                HISTORY:  In a hand-written note to Walter Retan dated 2/19/1968, David Paul writes: "We all goofed on the
                clock numbers, but H. Kane is fixing them and we will do the job right this time.  We all saw art and
                mechanicals, but we never saw blues.  In the future, it might be wise to see blues before the first proof."

                ADDITIONAL HISTORY OF INTEREST:  In an effort to give the book some "snap and difference", and as also
                mentioned in David Paul's note, the title was originally planned to curve around the clock dial.  In a type-written
                response to David Paul dated 2/26/1968, Walter Retan says that he still has proofs of the jacket (two versions)
                which he has discussed with Dick Krinsley.  Both men prefer that the title appear in a straight line as opposed to
                curving around the clock.  Walter also suggests that, "The lower part of the illustration could also be cropped to
                eliminate completely Jupiter's little brief case."

                  Harry Kane's original 1968 cover painting for "Screaming Clock".                                
                        Collection of Seth T. Smolinske, 2004-2012, now residing in a private collection.

#10 The Mystery of the Moaning Cave

Date Change:  In the last sentence of chapter 3 in all but one U.S. edition, El Diablo is said to have been 18 years old in 
                     1888.  The exception can be found in the 1978 Scholastic paperback where the year was changed to 1898.
                     [Thanks to Matthias Bogucki who shared this discovery with me on Sept. 21, 2012.  According to Matthias,
                      in the German editions, first published in 1974, the date is 1898.]

#11 The Mystery of the Talking Skull

Typo:  On page 157 of the hardback trade edition, third line from the bottom, "und" should be "and".

          HISTORY:  On Dec. 21, 1970 Peter Williamson of Princeton, New Jersey wrote a letter to Random House informing
          them of this error.  On Jan. 6, 1971, Emily Graham sent a letter of thanks to Peter and also sent a memo to Howard
          Goldstein to have this error corrected in the next printing of the book.  
          [Hardback trade editions listing 16 and more titles on the rear cover should contain the correction, titles with up to 14
          titles seem to all contain the error. -STS]

Trivia:  The postage rate increase that Pete mentions on page 122 (from five cents to six cents for a First Class letter)
           occurred on January 7, 1968, a few months before Robert Arthur began working on this book.
           [Thanks to Derrel Greer, 4-3-13.]

#12 Laughing Shadow

Text Error: On page 91 of the Random House hardback, the Marchesi paperback and the Hitchcock paperback editions, it
                 should be Pete, not Bob, who is mentioned in the line: "They'll probably be gone by now, sir, especially if the
                 shadow saw Bob and me last night."  Please refer to chapter 8 of the book for verification.
                 This error is found on page 95 of the Scholastic edition and page 80 of the Keyhole paperback edition.

Illustration Error:  The illustration on page 133 of the Random House hardback, the Marchesi paperback and the Hitchcock
                          paperback editions shows Jupiter and Pete but it should be Bob and Pete.
                          [Thanks to Philip Fulmer who first mentioned this on his site circa 2000.]

#14 Coughing Dragon

Incorrect Fact:  On page 157 of the Random House hardback Jupiter states that the government makes a large standard
                       gold bar which weighs 70 pounds and a small standard gold bar which weighs 20 pounds.  In actuality, the
                       U.S. government makes only one standard size gold bar and it weighs approximately 27.5 pounds.
                       [Thanks to Derrel Greer for pointing out this error on September 10, 2011.]
                       This incorrect information was not corrected in any later editions. -STS

#20 The Mystery of Monster Mountain

Text Error:  In the Keyhole Paperback Edition (Revised Edition, 1985) the last line of text on page 67 reads:  
                 against a tree trunk. "From the inn this mountain
                 This line is repeated again as the first line of text on page 68.
                 [Thanks to Jeffrey Ringel for discovering this error on August 15, 2011.]
                 The error is found in the first four printings, it was corrected in the 5th printing. -STS

#21 The Secret of the Haunted Mirror

Text Error:  In the beginning of Chapter 11, seventh sentence, it should be Pete, not Bob, who says "Red Gate Rover?"
                 This error appears to have not been corrected until the 1991 Bullseye paperback edition was published.
                 [Thanks to Mike Lillis for reporting this error on November 28, 2015.]

#24 The Mystery of Death Trap Mine

Incorrect Fact:  On pages 114/115 of the hardback trade and GLB edition, Jupiter suggests lighting a shack on fire to draw                          the police's attention, and it explodes because "Thurgood was keeping his dynamite in that shack."                                    However, dynamite does not explode when set on fire; it requires a shock (such as that delivered by a                                 blasting cap) to detonate. burning is actually a preferred method of disposing of old dynamite when you                               don't want to risk moving it.
                       [Thanks to Trey Wright for discovering this scientific error on February 27, 2013.]

#26 The Mystery of the Headless Horse

Text Error:  On page 43, line eleven, in First and Second printings of the hardback trade edition the following sentence 
                 is oddly repeated from page 41:  "All wet as usual," Skinny Norris called from the car
                 [Thanks to Pat Brooks for discovering this error in July of 2011.]
                 The line has been removed from page 43 in all later printings. -STS

#36 The Mystery of the Missing Mermaid

Typo:  One of the most egregious errors of them all, on page 4 Bob Andrews is referred to as Bob Reynolds!  The error is
          found in the GLB hardback, Keyhole paperback and Bullseye paperback editions and was never corrected.
          [This error's been known for a long time, I'm not sure when/where it was first mentioned but thanks to Ian Regan
           for reminding me of it on October 26, 2011.]

FYF#2 The Case of the Dancing Dinosaur

Incorrect Attribution:  Illustrator Gonzalez Vicente's name is wrongly spelled "Vincente" in all U.S. copies of this title.
                               [Thanks to Ian Regan for reminding me of this error on October 26, 2011.  Although it isn't evident to
                               readers, Vicente's original illustration for page 5 was rejected by the editor and replaced with a 
                               corrected drawing.  Both illustrations can be viewed HERE with thanks to Ian.]

FYF#7 The Case of the House of Horrors

Typo:  On page 97 of both the hardback and paperback editions, one of your choices is to turn to page 103.  This page is
          incorrect, the correct page to turn to for this choice is 115.
          [Thanks to Lori for sharing this in post #308.1 of The Jones Salvage Yard Forum.]
Oh my, this old scan is a bit muddy but you can see how the book cover turned out.