How is Watson portrayed throughout the novella (include quotations)?

From the very beginning of the story, Watson is portrayed as having enormous respect for Holmes. The Sign of Four starts with Holmes injecting himself with cocaine, as is his normal habit. Yet, no matter how many times he witnesses this elaborate ritual, Watson continues to find it an unpleasant sight:

Three times a day for many months I had witnessed this performance, but custom had not reconciled my mind to it.

Watson feels that he really should say something about Holmes's drug addiction, but he is much too respectful of Holmes to contemplate doing so:

His great powers, his masterly manner, and the experience which I had had of his many extraordinary qualities, all made me diffident and backward in crossing him.

As well as being a considerate friend to Holmes, Watson also proves to be a profoundly honorable man. He falls deeply in love with Mary Morstan, but he worries that people will think he is after her money. He does not want Mary to have to deal with their snide insinuations. However, when the treasure is lost, the question of Mary's inheritance is no longer an issue. Now Watson can express his true feelings for Mary:

Because I love you, Mary, as truly as ever a man loved a woman. Because this treasure, these riches, sealed my lips. Now that they are gone I can tell you how I love you. That is why I said, "Thank God."

This leads us to another characteristic of Watson: his romanticism. In this respect, Watson is very different from Holmes, with his cold reason and unerring logic. Accordingly, it comes as no surprise that Holmes chides Watson for his romantic style in writing "A Study in Scarlet":

Honestly, I cannot congratulate you upon it. Detection is, or ought to be, an exact science, and should be treated in the same cold and unemotional manner. You have attempted to tinge it with romanticism, which produces much the same effect as if you worked a love-story or an elopement into the fifth proposition of Euclid.

Finally, Watson is presented as being incredibly loyal. One dark, foggy night, Watson finds himself with Holmes and Miss Morstan in a hansom cab rattling through the streets of London. He has no idea where they are going or even why they are going there. However, Watson trusts Holmes implicitly. However strange and potentially dangerous a situation may be, Watson knows that he can always count on his famous friend:

I lost my bearings, and knew nothing, save that we seemed to be going a very long way. Sherlock Holmes was never at fault, however, and he muttered the names as the cab rattled through squares and in and out by tortuous by-streets.