Both texts are murder mysteries but there is a single important difference. In TSB we are encouraged to find the solution to the murder by assembling our evidence from the text and drawing conclusions as we see fit. There is, though, a red herring clue included to throw the reader, the most obvious example being the presence and the close association of the Gypsies with Dr Roylott. In LTTS we know who has committed the murder and the details, but the fun is in seeing if she will get caught. Both pieces of text have unusual murder weapons but this is a norm with murder mysteries which continues to this day; the Jonathon Creek series being a popular notable example.
The characters in both texts are well worth a mention. In TSB the characters are predictable. The strong, brutal male, Dr Roylott is the murderer and the emphasis is less on who and more on how. I dont think that Sir Arthur Doyle would be allowed to get away with this in either the present day climate or the climate of 1954. Just as Dr Roylott is an obvious murder suspect Helen Stoner is the obvious damsel in distress. The dragged out description of her and her features describe a woman with a figure of thirty but starting to sprout premature grey hair.
In TSB the characters are subject to a much longer introduction and time of description. Rhoald Dahl does not do this and hardly describes Mary Maloneys physical appearance at all leaving each individual reader to draw his or her image. The reader though cannot disagree on the mindset of Mary Maloney; she is obsessed with her husband and routines. Even though TSB is written in the first person I think we can still tell more about Mary Maloneys character. Sir Arthur Doyle has not delved too deeply into Dr Watsons thoughts and this is deliberate. The only think that Sir Arthur Doyle concentrates on in Dr Watsons subconscious mind is his admiration of Sherlock Holmes, after all they are the Sherlock Holmes series of books and Dr Watson is only a clever literary narrative tool.
In LTTS the characters are less predictable. We know that Sir Arthur Doyle did once try to make his characters actions unpredictable to the extreme by killing off Sherlock Holmes but the pressure of public opinion forced him to resurrect his most famous character. The murderer this time is not the brutal male but the supposedly timid housewife. Notice also that the sex of the murderer has changed. It would be fair to say that this would mirror a change in the opinion of the role of women, there gaining of the vote and there rise to equals of the male sex.
The feelings and sympathies we have with the murderers is also worthy of attention. We feel sorry for Mary Maloney up to a point in LTTS because she is six months pregnant and we sympathise with her shock and we recognise that her murder was more of a spur of a moment murder rather than a carefully constructed and well executed murder plot as is the case with DR Roylott. The point where I no longer feel sympathetic was when she laughed at the very end of the text. This displayed a deeper evil that had gone unnoticed before in the text.
The feelings we feel for the victims are very different. In TSB we feel sorry for the victim in the text, Helen Stoners sister, who is in the prime of her life and is about to get married. This increases our hatred of Dr Roylott. The victim in LTTS is a man who is leaving his wife who is six months pregnant. His conduct up to the point of his death is rude and arrogant. He uses monosyllabic answers to firmly control his wife. Also when he leaves his wife he is more worried about the effect it may have on his job. We are not too sorry to see him go.
The two pieces do have a number of similarities. They both have unusual murder weapons and they both remind us that even respectable, or in the case of Dr Roylott once respectable members of the community can kill, whether that is because of financial or personal reasons. They share common themes such as murder, murder mystery and deceit.