A Spider's Web

“And they went further and further from her, being attached to her by a thin thread (since they lunched with her) which would stretch and stretch, get thinner and thinner as they walked across London; as if one's friends were attached to one's body, after lunching with them, by a thin thread, which (as she dozed there) became hazy with the sound of bells, striking the hour or ringing to service, as a single spider's thread is blotted with rain-drops, and, burdened, sags down. So she slept. And Richard Dalloway and Hugh Whitbread hesitated at the corner of Conduit Street at the very moment that Millicent Bruton, lying on the sofa, let the thread snap; snored” (Woolf 112)

In this section, Woolf describes the bonds between people as as threads which connect us all. She writes that the threads become "hazy" with bells "striking the hour," meaning that as time goes on, friendships fade. This implies that Hugh and Richard's friendship with Lady Bruton will fade also. Additionally, this parallels how Clarissa's feelings for Peter Walsh have faded as time passed and how Rezia's feelings for Septimus have faded as well. Woolf compares the slow process of bonds diminishing to a "spider's thread...blotted with rain-drops" that ultimately sags under the burden of them. Time is represented through the raindrops, which alone do not seem heavy but accumulated have more force than expected. Through this simile Woolf illustrates that time can easily drag down the thin threads of friendship. 
Woolf uses language related to spiders frequently in this passage, making Lady Bruton herself seem like a spider. She attaches a "thin thread" to each of her friends to form a web of connections, that she can control at will. For example, she "let the thread snap" between her, Hugh, and Richard, breaking off their bond. Her position of control reflects her ancestors, many being generals. Lady Bruton did not follow their legacy, but she still has her own soldiers to command.