手之六阳经脉从手至头，长五尺，共计五六合三丈。
手之六阴经脉从胸走手，长三尺五寸，共计三六一丈八尺，五六合三尺，合二丈一尺。
足之六阳经脉从头走至足，长八尺，共计六八四丈八尺。
足之六阴经脉从足走入胸中，长六尺五寸，共计六六三十六，五六当三尺，合三丈九尺。
督脉、任脉各长四尺五寸，共合九尺。
两跷脉从足至目，各长七尺五寸，共合一丈五尺。
十四脉都合十六丈二尺，此气之大经隧也。
夫所谓经者，以其气血流行之大经常而不息者。谓之脉者，以其血理分袤（音谋，言相去也。）
行体者而言也。谓之络者，本经之旁支而别出以联系于十二经者也。如手太阴经之支者，从腕后
出次指端而交于阳明经者是也。
\r中指同身寸图\ps127a60.bmp\r
凡量四肢穴道必用此中指寸法，盖四肢长短无不同者。量身上穴当同身。
男左女右，手中指第二内廷两横纹头相去为一寸，取稻秆心量，或用薄篾量，皆易折而不伸
缩为准，用绳则伸缩不便，故多不准。
\r肺脏形图\ps127a61.bmp\r
\r手太阴肺经穴图\ps127a62.bmp\r
《内经》曰∶西方白色，入通于肺，开窍于鼻，藏精于肺，故病在背。其味辛，其类金，其
畜马，其谷稻，其音商，其数九，其臭腥，其液涕。肺主鼻，其在天为燥，在地为金，在体为皮
毛，在脏为肺，在色为白，在音为商，在声为哭，在变动为咳，在窍为鼻，在味为辛，在志为忧。
忧伤肺，喜胜忧。热伤皮毛，寒胜热。辛
伤皮毛，苦胜辛。其应四时，上为太白星。是以知病之在皮毛也。
肺者，气之本，魄之处也，其华在毛，其充在皮，为阳中之太阳，通于秋气。
肺者，相傅之官，治节出焉。肺之合皮也，其荣毛也，其主心也。肺色白，欲如鹅毛，不欲如盐。
肺气绝则皮毛焦，皮毛焦则津液去，津液去则皮节伤，皮节伤则皮枯毛折，毛折者死不治。
手太阴肺脉起于中焦，下络大肠，还循胃口，上膈属肺，从肺系（喉咙是也）横出腋下，循
内，行少阴心主之前，下肘中，循臂内上骨下廉，入寸口，上鱼，循鱼际，出大指之端，其支者，
从腕后直出次指内廉，出其端。凡十一穴，左右共二十二穴。
手部的六条阳经，从手部走向头部，每条长五尺，合计六条经脉共三丈。
手部的六条阴经，从胸部走向手部，每条长三尺五寸，合计六条经脉一丈八尺，加上与阳经计算时多出的三尺，总计二丈一尺。
足部的六条阳经，从头部走向足部，每条长八尺，合计六条经脉四丈八尺。
足部的六条阴经，从足部走入胸部，每条长六尺五寸，合计六条经脉三丈九尺。
督脉和任脉各长四尺五寸，合计九尺。
两条跷脉（阳跷脉、阴跷脉）从足部走向眼部，各长七尺五寸，合计一丈五尺。
这十四条经脉总共长十六丈二尺，这是人体气血运行的大通道。
所谓“经”，是指气血流行的大道，其运行规律且不停息。所谓“脉”，是从血液纹理在体内分布运行的角度而言的。所谓“络”，是本经的旁支，别出以联系十二正经的脉络。例如手太阴肺经的支脉，从手腕后出，到达食指末端并交于阳明经，就是这种情况。
凡测量四肢穴位必须使用这种“中指同身寸”法，因为四肢的长度没有不同之处。测量身上穴位则应使用个人的同身寸。取法为：男子取左手，女子取右手，手中指第二节内侧两个横纹头之间的距离为一寸。可用稻秆心或薄竹篾来量取，以容易折断而不伸缩为准；如果用绳子，因伸缩不便，所以往往不准确。
《黄帝内经》说：西方对应白色，内通于肺，开窍于鼻，精气藏于肺，所以病变常反映在背部。肺对应的味道是辛，五行属性为金，家畜对应马，谷物对应稻，音律对应商，成数对应九，气味对应腥，体液对应涕。肺主管鼻子，在天象上对应燥气，在地形上对应金属，在形体上对应皮毛，在脏腑中对应肺，在面色上对应白色，在音律上对应商，在声音上对应哭，在变动上对应咳嗽，在孔窍上对应鼻，在味道上对应辛，在情志上对应忧。忧伤肺，喜悦可以克服忧伤。热邪损伤皮毛，寒邪可以克制热邪。辛味损伤皮毛，苦味可以克制辛味。肺应合四季中的秋季，在天上的星宿对应太白星。因此可以知道病位在皮毛。
肺，是气的根本，魄所居之处，其荣华表现于毛发，其充养在于皮肤，属于阳中之太阳，与秋气相通。
肺，如同宰相之官，治理调节全身功能由此产生。肺与皮相合，其荣华在毛，受心的制约。肺的颜色应为白色，像鹅毛一样润泽，不像盐那样枯白。如果肺气衰竭，则皮毛干枯，皮毛干枯则津液耗损，津液耗损则皮肤关节受损，皮肤关节受损则皮肤枯槁、毛发折断，毛发折断者死，无法救治。
手太阴肺经的脉气起始于中焦，向下联络大肠，回转沿着胃的上口，向上穿过膈肌，属于肺脏，从肺系（即喉咙）横向出于腋下，沿上臂内侧下行，走在手少阴心经和手厥阴心包经的前面，下行至肘中，沿前臂内侧桡骨下缘，进入寸口，上行至鱼际，沿鱼际边缘，出于大拇指尖端。其支脉，从手腕后方直出食指内侧边缘，到达其末端。共有十一个穴位，左右两侧共二十二个穴位。
The six Yang meridians of the hand run from the hand to the head, each measuring five chi, totaling three zhang (ten chi) for all six.
The six Yin meridians of the hand run from the chest to the hand, each measuring three chi and five cun, totaling one zhang and eight chi for all six; adding the extra three chi from the calculation with the Yang meridians, the total is two zhang and one chi.
The six Yang meridians of the foot run from the head to the foot, each measuring eight chi, totaling four zhang and eight chi for all six.
The six Yin meridians of the foot run from the foot into the chest, each measuring six chi and five cun, totaling three zhang and nine chi for all six.
The Du Mai (Governing Vessel) and Ren Mai (Conception Vessel) each measure four chi and five cun, totaling nine chi.
The two Qiao Mai (Yang and Yin Heel Vessels) run from the foot to the eye, each measuring seven chi and five cun, totaling one zhang and five chi.
These fourteen meridians together measure sixteen zhang and two chi; these are the great channels through which Qi flows.
The term "Jing" (Meridian) refers to the major pathways where Qi and Blood flow continuously and rhythmically. The term "Mai" (Vessel) refers to the blood vessels based on their distribution and course within the body. The term "Luo" (Collateral) refers to the side branches of the main meridians that diverge to connect with the twelve regular meridians. For example, the branch of the Hand-Taiyin Lung Meridian emerges from behind the wrist, reaches the tip of the index finger, and connects with the Yangming Meridian.
When measuring acupoints on the limbs, this "Middle Finger Same-Body Cun" method must be used, as limb lengths are consistent among individuals. When measuring acupoints on the trunk, one's own body proportions should be used. The method is: for men, use the left hand; for women, use the right hand. The distance between the two transverse creases at the middle joint of the middle finger constitutes one cun. One may use the pith of a rice stalk or a thin bamboo splint for measurement, ensuring it breaks easily without stretching or shrinking. If rope is used, its tendency to stretch makes it inaccurate.
The *Neijing* states: The West corresponds to white, internally connecting to the Lung, opening into the nose, storing essence in the Lung, so diseases often manifest in the back. Its flavor is pungent, its element is Metal, its animal is the horse, its grain is rice, its musical note is Shang, its number is nine, its odor is fishy, and its fluid is mucus. The Lung governs the nose; in nature, it corresponds to Dryness; in earth, to Metal; in the body, to skin and hair; in the zang-fu, to the Lung; in color, to white; in sound, to Shang; in vocalization, to crying; in pathological change, to coughing; in orifice, to the nose; in flavor, to pungent; and in emotion, to sorrow. Sorrow damages the Lung, while Joy overcomes Sorrow. Heat damages skin and hair, while Cold overcomes Heat. Pungency damages skin and hair, while Bitterness overcomes Pungency. It corresponds to the four seasons, specifically Autumn, and in the heavens, to the planet Venus (Tai Bai). Thus, one can know that disease resides in the skin and hair.
The Lung is the root of Qi and the residence of Po (Corporeal Soul); its brilliance manifests in the hair, and it nourishes the skin. It is considered Taiyang within Yang, communicating with the Qi of Autumn.
The Lung is like the Prime Minister, responsible for regulation and coordination. The Lung harmonizes with the skin, its brilliance is in the hair, and it is controlled by the Heart. The color of the Lung should be white, resembling goose feathers (lustrous), not salt (dull). If Lung Qi is exhausted, the skin and hair become dry; if dry, fluids are lost; if fluids are lost, the skin joints are damaged; if damaged, the skin becomes withered and hair breaks. If hair breaks, death occurs and cannot be cured.
The pulse of the Hand-Taiyin Lung Meridian originates in the Middle Jiao, descends to connect with the Large Intestine, returns along the stomach opening, ascends through the diaphragm, and enters the Lung. From the Lung system (the throat), it emerges horizontally under the axilla, runs down the medial aspect of the arm, anterior to the Shaoyin Heart and Jueyin Pericardium meridians, descends to the elbow, follows the medial aspect of the forearm along the lower border of the radius, enters the Cun Kou (radial artery pulse point), ascends to the Thenar eminence (Yu Ji), follows the border of the thenar eminence, and emerges at the tip of the thumb. Its branch emerges straight from behind the wrist to the medial side of the index finger, reaching its tip. There are eleven acupoints on this meridian, totaling twenty-two points on both sides.