What effect do these adjectives from A Christmas Carol have on the reader? Scrooge is "a squeezing, wrenching, grasping, scraping, clutching, covetous, old sinner."
By putting this list adjectives describing Scrooge so close to the beginning of the story, Dickens establishes our impression early on of Scrooge as a distinctly unpleasant man. As for particular techniques Dickens uses, the first relies on the sounds of the words—all have a guttural, grinding quality. These are words you can hear and feel—harsh words. As such they convey a physical sensation of what Scrooge's hard soul is like. Second, they symbolize the rough, scraping, heavy chain that we will soon find out that Scrooge has been forging all these years, just as Marley did, through his behaviors of grasping and clutching at money.
We can also see that this pile up of adjectives reflects the metallic piling up of money that Scrooge has amassed over the years. Further, by putting this list of adjectives in the context of the paragraph in which they appear, we perceive Dickens' use of another technique: alliteration, or using the same first consonant repeatedly in the same line or lines:
Oh! but he was a tight-fisted hand at the grindstone, Scrooge! a squeezing, wrenching, grasping, scraping, clutching, covetous, old sinner! Hard and sharp as flint, from which no steel had ever struck out generous fire; secret, and self-contained, and solitary as an oyster. The cold within him froze his old features, nipped his pointed nose, shrivelled his cheek, stiffened his gait; made his eyes red, his thin lips blue; and spoke out shrewdly in his grating voice. A frosty rime was on his head, and on his eyebrows, and his wiry chin. He carried his own low temperature always about with him; he iced his office in the dog-days; and didn't thaw it one degree at Christmas.
In this larger context, we read the alliteration in grindstone and grasping, and in Scrooge, squeezing, scraping, sinner, steel, struck, secret and self-contained.
All of these words have a relentlessly harsh or hissing effect, which leads the reader to understand Scrooge as a hard-hearted man through and through.