public function lines($page = null)
    {
        $url = sprintf('buckets/%d/chats/%d/lines.json', $this->bucket, $this->parent);

        $lines = $this->client->get($url, [
            'query' => [
                'page' => $page,
            ]
        ]);

        return $this->indexResponse($lines, CampfireLine::class);
    }