Even though the description of Tom is quite objective, the sunshine and clearness has a high symbolic importance to the passage and makes it more of a contrast to the other passage. This sunshine could be there because Tom is an antagonist in the novel, thus his description should not be complicated as, for example Gatsby's. Thereby he is connected to unambiguousness, whereas Gatsby is connected to darkness and implying that his character will be revealed later on.
The sunshine which is connected to Tom could mean that his character is exposed and open for everyone to look at. This could be connected to that his characteristics are those of a fascist prototype that have nothing to hide and are proud to show themselves anywhere they go. This personality which Tom is part of does also seem quite primitive and animalistic: He does what his needs and emotions demands of him and he does not seem to hide secrets. This compared to the character of Gatsby which seems to be more complicated and untrustworthy. Tom is a more physical than mental character.
Gatsby is on the other hand connected to the night and is a therefore a contrast to Tom. When Tom can be seen in the light, Gatsby "vanishes" in the dark. Hence he is a mysterious character, like a cat and it is interesting to note that there is a cat included in the passage: "The silhouette of a moving cat wavered across the moonlight..." Gatsby is definitely like a cat; a creature of the night, unidentified and unique. Tom is conversely more of a dog: Strong but more primitive.
In both passages the author uses cohesive devices to support the respective themes. There is plenty of personification in the first passage: "shining...arrogant eyes", "cruel body" and these have the effect of making Tom's character living. The negative words give more strength in making Tom a brutal man. The second passage includes more symbolism and metaphors can be found: "the full bellows of the earth blew the frogs full of life" and of course the connection of Gatsby and the cat is important. The effect of the techniques on both passages are clear: They are the key instrument in creating the themes and the moods in the first hand.
Another important matter to the passages is the environmental descriptions. After the description of Tom's body one finds out some things about his home. It is worthy of note that his possessions are given the same, quite negative adjectives as his body got: "sunken Italian garden", "snub-nosed motor-boat". Perhaps this is attempt by the author to strengthen the readers view of Tom as a "cruel" man.
In general, both passages are descriptive and important to the novel as they portray two very central characters in the novel. Nonetheless, the passages are quite dissimilar as far as the themes, tones and techniques are concerned. The contrasting themes are day and night and the tone and the techniques are based around these themes. The techniques are quite different in the two passages; in Toms there are many negative words and his body is personified as "cruel". In Gatsby's passage there are more words connected to obscurity and Gatsby is not at all illustrated negatively. The techniques create two contrasting moods in the two passages. Tom's passage is more simple and it is not as interesting to read as Gatsby's passage. Tom's passage is almost unpleasant to read because one could almost think he is a monster by his account. The tone in Gatsby's passage is more calm. The presence of the night makes everything more subjective and abstract. A potential effect of this is that the reader will feel more comfortable with this passage. Things connected to the night are usually more interesting.
