谈判函件发出去的第三天，陈景行没有等来苏红棉的正式回复，便亲自去了城东货运站。
她没有再穿那件米色风衣，换了一身灰蓝色的户外装束，脚踩登山鞋，背包侧兜插着一只折叠工兵铲。她没戴任何标识身份的东西，但陆岩在她出现在货运站门口的第一时间就认出了她。青囊卫的暗线从植物园跟到货运站，又跟到了那排梧桐树下面。
陈景行在梧桐树前蹲了很久。她没碰树根，也没碰地面的根须——她只是用一根细钢签在离树根三寸远的地方轻轻探了探泥土，然后把钢签抽出来放在鼻端嗅了嗅，又取出一只微型温度计插进土里。整个过程安静而专业，像个做田野调查的研究员，而不是来搞事的人。
但她还是被盯上了。
陈大勇亲自带的暗线，两个青囊卫扮成搬运工坐在货运站门口抽烟，另一个扮成环卫工推着垃圾车在绿化带附近来回走了两趟。陈景行从梧桐树前站起来时朝四周扫了一眼，目光在“搬运工”身上停了不到一息便移开了，然后朝城北方向走去。陈大勇没有让人继续跟——苏红棉交代过，跟得太紧反而暴露暗线的存在。
当天傍晚，陈景行又出现在了城北老工业区的水塔下面。她花了将近半个时辰围着塔基转了两圈，最后在水塔东侧的地面上蹲下，钢签探入碎石缝中取了一点土样。这次她没有多停留，天没黑就打车回了市区方向。
苏红棉在诊室里听完陈大勇的汇报后没有说话，只是把探龙针从桌上拿起，在墙上地图的水塔位置画了一个圈，又在梧桐树的位置画了一个圈。两个圈之间连了一条虚线。
“她在做地脉走向的初步勘测。”苏红棉把探龙针放下，“梧桐树在城东，水塔在城北，两个点之间的直线距离将近四公里。她选的这两个位置，恰好位于地母根第七节和第三节支管的末梢之间。如果她把这四个点连起来，就能大致画出地脉管网在城区的分布轮廓。”
“她能看到根须吗？”陆岩问。
“肉眼看不到。但她的钢签能探到土壤温度异常，温度计能测出地温升高的范围。只要她在足够多的点位取样，就能反推出地下根须的走向和分布范围。”苏红棉顿了顿，“陈氏研究地脉灵气与植物生长相互作用的人，本来就是干这个的。他们有一套成熟的野外勘测方法，不靠灵气感知，靠的是土壤学、地质学和植物生理学。”请求出错，状态码:0内容:请求出错，状态码:502内容:<!DOCTYPE html>
<!--[if lt IE 7]> <html class="no-js ie6 oldie" lang="en-US"> <![endif]-->
<!--[if IE 7]> <html class="no-js ie7 oldie" lang="en-US"> <![endif]-->
<!--[if IE 8]> <html class="no-js ie8 oldie" lang="en-US"> <![endif]-->
<!--[if gt IE 8]><!--> <html class="no-js" lang="en-US"> <!--<![endif]-->
<head>
<title>biqugem.com | 502: Bad gateway</title>
<meta charset="UTF-8" />
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />
<meta http-equiv="X-UA-Compatible" content="IE=Edge" />
<meta name="robots" content="noindex, nofollow" />
<meta name="viewport" content="width=device-width,initial-scale=1" />
<link rel="stylesheet" id="cf_styles-css" href="/cdn-cgi/styles/main.css" />
</head>
<body>
<div id="cf-wrapper">
<div id="cf-error-details" class="p-0">
<header class="mx-auto pt-10 lg:pt-6 lg:px-8 w-240 lg:w-full mb-8">
<h1 class="inline-block sm:block sm:mb-2 font-light text-60 lg:text-4xl text-black-dark leading-tight mr-2">
<span class="inline-block">Bad gateway</span>
<span class="code-label">Error code 502</span>
</h1>
<div>
Visit <a href="https://www.cloudflare.com/5xx-error-landing?utm_source=errorcode_502&utm_campaign=www.biqugem.com" target="_blank" rel="noopener noreferrer">cloudflare.com</a> for more information.
</div>
<div class="mt-3">2026-09-23 06:21:23 UTC</div>
</header>
<div class="my-8 bg-gradient-gray">
<div class="w-240 lg:w-full mx-auto">
<div class="clearfix md:px-8">
<div id="cf-browser-status" class=" relative w-1/3 md:w-full py-15 md:p-0 md:py-8 md:text-left md:border-solid md:border-0 md:border-b md:border-gray-400 overflow-hidden float-left md:float-none text-center">
<div class="relative mb-10 md:m-0">
<span class="cf-icon-browser block md:hidden h-20 bg-center bg-no-repeat"></span>
<span class="cf-icon-ok w-12 h-12 absolute left-1/2 md:left-auto md:right-0 md:top-0 -ml-6 -bottom-4"></span>
</div>
<span class="md:block w-full truncate">You</span>
<h3 class="md:inline-block mt-3 md:mt-0 text-2xl text-gray-600 font-light leading-1.3">
Browser
</h3>
<span class="leading-1.3 text-2xl text-green-success">Working</span>
</div>
<div id="cf-cloudflare-status" class=" relative w-1/3 md:w-full py-15 md:p-0 md:py-8 md:text-left md:border-solid md:border-0 md:border-b md:border-gray-400 overflow-hidden float-left md:float-none text-center">
<div class="relative mb-10 md:m-0">
<a href="https://www.cloudflare.com/5xx-error-landing?utm_source=errorcode_502&utm_campaign=www.biqugem.com" target="_blank" rel="noopener noreferrer">
<span class="cf-icon-cloud block md:hidden h-20 bg-center bg-no-repeat"></span>
<span class="cf-icon-ok w-12 h-12 absolute left-1/2 md:left-auto md:right-0 md:top-0 -ml-6 -bottom-4"></span>
</a>
</div>
<span class="md:block w-full truncate">Hong Kong</span>
<h3 class="md:inline-block mt-3 md:mt-0 text-2xl text-gray-600 font-light leading-1.3">
<a href="https://www.cloudflare.com/5xx-error-landing?utm_source=errorcode_502&utm_campaign=www.biqugem.com" target="_blank" rel="noopener noreferrer">
Cloudflare
</a>
</h3>
<span class="leading-1.3 text-2xl text-green-success">Working</span>
</div>
<div id="cf-host-status" class="cf-error-source relative w-1/3 md:w-full py-15 md:p-0 md:py-8 md:text-left md:border-solid md:border-0 md:border-b md:border-gray-400 overflow-hidden float-left md:float-none text-center">
<div class="relative mb-10 md:m-0">
<span class="cf-icon-server block md:hidden h-20 bg-center bg-no-repeat"></span>
<span class="cf-icon-error w-12 h-12 absolute left-1/2 md:left-auto md:right-0 md:top-0 -ml-6 -bottom-4"></span>
</div>
<span class="md:block w-full truncate">www.biqugem.com</span>
<h3 class="md:inline-block mt-3 md:mt-0 text-2xl text-gray-600 font-light leading-1.3">
Host
</h3>
<span class="leading-1.3 text-2xl text-red-error">Error</span>
</div>
</div>
</div>
</div>
<div class="w-240 lg:w-full mx-auto mb-8 lg:px-8">
<div class="clearfix">
<div class="w-1/2 md:w-full float-left pr-6 md:pb-10 md:pr-0 leading-relaxed">
<h2 class="text-3xl font-normal leading-1.3 mb-4">What happened?</h2>
<p>The web server reported a bad gateway error.</p>
</div>
<div class="w-1/2 md:w-full float-left leading-relaxed">
<h2 class="text-3xl font-normal leading-1.3 mb-4">What can I do?</h2>
<p class="mb-6">Please try again in a few minutes.</p>
</div>
</div>
</div>
<div class="cf-error-footer cf-wrapper w-240 lg:w-full py-10 sm:py-4 sm:px-8 mx-auto text-center sm:text-left border-solid border-0 border-t border-gray-300">
<p class="text-13">
<span class="cf-footer-item sm:block sm:mb-1">Cloudflare Ray ID: <strong class="font-semibold">a3f772ec3ae4e2ec</strong></span>
<span class="cf-footer-separator sm:hidden">•</span>
<span id="cf-footer-item-ip" class="cf-footer-item hidden sm:block sm:mb-1">
Your IP:
<button type="button" id="cf-footer-ip-reveal" class="cf-footer-ip-reveal-btn">Click to reveal</button>
<span class="hidden" id="cf-footer-ip">43.243.73.188</span>
<span class="cf-footer-separator sm:hidden">•</span>
</span>
<span class="cf-footer-item sm:block sm:mb-1"><span>Performance & security by</span> <a rel="noopener noreferrer" href="https://www.cloudflare.com/5xx-error-landing?utm_source=errorcode_502&utm_campaign=www.biqugem.com" id="brand_link" target="_blank">Cloudflare</a></span>
</p>
<script>(function(){function d(){var b=a.getElementById("cf-footer-item-ip"),c=a.getElementById("cf-footer-ip-reveal");b&&"classList"in b&&(b.classList.remove("hidden"),c.addEventListener("click",function(){c.classList.add("hidden");a.getElementById("cf-footer-ip").classList.remove("hidden")}))}var a=document;document.addEventListener&&a.addEventListener("DOMContentLoaded",d)})();</script>
</div><!-- /.error-footer -->
</div>
</div>
</body>
</html>