先君子体羸善病。故海早岁即习方书。有恙辄调治之。癸酉六月。骤得吐血。继复转为下血。查照各书。施
治罔效。延请名宿。仍无确见。大约用调停之药。以俟病衰而已。因此遍览方书。每于血证。尝三致意。时里
中人甚诩乡先辈杨西山先生所着失血大法。得血证不传之秘。门下钞存。私为鸿宝。吾以先君病。故多
方购求。仅得一览。而其书议论方药。究亦未能精详。以之治病。卒鲜成效。乃废然自返。寝馈于内经仲景
之书。触类旁通。豁然心有所得。而悟其言外之旨。用治血证。十愈七八。今先君既逝。而荆妻冯氏又得血
疾。亲制方剂。竟获安全。慨然曰。大丈夫不能立功名于天下。苟有一材一艺。稍足补救于当时。而又吝不
忍传。陋哉。爰将失血之证。精微奥义。一一发明。或伸古人所欲言。或补前贤所未备。务求理足方效。不为
影响之谈。书成自顾。而转憾悟道不早。不能延吾父之寿也。然犹幸此书之或可以救天下后世也。
光绪十年甲申重九后一日容川唐宗海自序
一、血证自古绝少名论。故是书条分缕析。务求精详。间有烦文冗字。意取明显。故不删削。
一、时贤论及血证。率多影响。是书独从内难仲景探源而出。发挥尽致。实补唐以下医书之所不逮。故
除引经之外。余无采录。亦间有一二暗合者。皆系偶同。并非掠美。识者鉴之。
一、是书分别门类。眉目极清。即不知医者。临时查阅。无不了然。最便世用之书。
一、是书议论多由心得。然其发明处。要皆实事实理。有凭有验。或从古圣引伸。或从西法参得。信而有
征之说也。并非杜撰可比。
一、是书单为血证说法。与杂证不同。幸勿执彼例此。亦幸勿以此议彼。
我的父亲身体瘦弱，容易生病。所以我从小就开始学习医书。每当他身体不适，我就为他调理治疗。癸酉年六月，他突然患上吐血病，随后又转为便血（下血）。我查阅参考各种医书，施治都没有效果。请来著名的老医生诊治，仍然没有确切的见解。大概只是用调和性质的药物，等待病情自然衰退罢了。因此，我遍览所有医书，每次遇到血证（以出血为主要表现的疾病），都格外用心研究。当时乡里人非常推崇乡先辈杨西山先生所著的《失血大法》，认为它掌握了血证不传的秘诀，门徒们抄录保存，私下视为珍宝。我因为父亲的病，多方购买寻求，仅得以浏览一遍。但该书在议论和方药方面，终究未能做到精详。用它来治病，最终很少见效。于是我不甘心地返回，潜心研读《内经》和《伤寒杂病论》（仲景之书），触类旁通，心中豁然开朗有所领悟，并领会其言外之意。用这些方法治疗血证，十次能治愈七八次。如今父亲已经去世，而我的妻子冯氏又得了血疾，我亲自配制方剂，竟然使她平安无事。我不禁感慨道：大丈夫如果不能在天下建立功业名声，如果有一技之长，稍微足以补救于当时，却又吝惜不肯传授，这也太浅陋了。于是我将失血证的精微奥义，一一阐明。有的阐发古人想要说而未说出的道理，有的补充前贤所未备的内容，务必追求理论充足、方剂有效，不做虚浮无据的谈论。书成之后，我回顾自身，反而遗憾悟道太晚，不能延长我父亲的寿命。然而仍庆幸这本书或许可以救治天下后世的人。
光绪十年甲申年重阳节后一天，容川唐宗海自序
一、血证自古以来极少有著名的论述。所以本书条理分明，务求精密详尽。间或有繁琐的文字和冗长的字句，意在取明显易懂，所以不予删减。
一、当时的学者讨论血证，大多虚浮不实。本书唯独从《内经》、《难经》和《伤寒杂病论》探求本源而出，发挥得淋漓尽致，确实弥补了唐代以后医书的不足。所以除了引用经典之外，其余没有采纳其他书籍的内容。也间或有一两处暗中契合的，都是偶然相同，并非掠取他人之美。明眼人自会鉴别。
一、本书分别门类，条理极其清晰，即使是不懂医学的人，临时查阅，也没有不明白的。是最便于世人使用的书。
一、本书的议论多由心得而来，但其发明之处，都是实事实理，有凭有据，有验证。有的是从古圣先贤引申而来，有的是从西方医学方法参悟得到，是可信且有证据的说法。并不是杜撰可比拟的。
一、本书专门论述血证，与杂证不同。希望不要拿其他病症的例子来套用，也希望不要用其他病症来议论本书。
My father had a frail constitution and was prone to illness. Therefore, I studied medical texts from an early age. Whenever he fell ill, I would regulate his treatment. In the sixth month of the Guiyou year, he suddenly suffered from hematemesis (vomiting blood), which subsequently progressed to hematochezia/melena (bleeding from the lower orifice). Consulting various medical books, my treatments proved ineffective. I invited renowned senior physicians, yet they still lacked definitive insights. Generally, only harmonizing medications were used, waiting for the disease to subside naturally. Consequently, I perused all medical texts, paying particular attention to each instance of Blood Disease (diseases characterized primarily by bleeding). At that time, locals highly praised Mr. Yang Xishan, a local predecessor, for his work *Shi Da Fa* (Great Method for Loss of Blood), claiming it contained the secret transmission for treating Blood Disease, which his disciples copied and preserved as a private treasure. Due to my father's illness, I sought and purchased copies extensively, managing only to glance through one. However, its discussions on principles and prescriptions were ultimately not precise and detailed enough. Using it for treatment yielded few results. Thus, I returned in disappointment, immersing myself in the study of the *Neijing* (Inner Canon) and the works of Zhang Zhongjing. Through analogical reasoning, I experienced a sudden enlightenment and grasped the implicit meanings, applying these methods to treat Blood Disease with a success rate of seven or eight out of ten cases. Now that my father has passed away, and my wife, Lady Feng, has contracted a Blood Disease, I personally prepared prescriptions, which successfully ensured her safety. I sighed, "If a great man cannot achieve merit and fame in the world, but possesses even a single skill sufficient to remedy the times, yet is too stingy to transmit it, how shallow is this!" Therefore, I have elucidated the subtle and profound principles of loss-of-blood syndromes one by one. I either expounded upon what ancient sages intended to say but did not, or supplemented what previous experts had left incomplete, striving for sound theory and effective formulas, avoiding baseless speculation. Upon completing the book, I reflected on myself and regretted that my understanding of the Dao came too late to extend my father's life. Yet, I am fortunate that this book might save people in the world and future generations.
Preface by Tang Zonghai, Rongchuan, written one day after the Double Ninth Festival of the Jia Shen year, 10th Year of Guangxu (1884)
1. Famous discussions on Blood Disease are rare since ancient times. Therefore, this book analyzes the subject meticulously, aiming for precision and detail. Although there are occasionally verbose passages, the intent is clarity; thus, they are not deleted.
2. Contemporary scholars' discussions on Blood Disease are often superficial. This book uniquely traces its origins to the *Neijing*, *Nanjing*, and Zhang Zhongjing's works, exploring them thoroughly. It truly compensates for the deficiencies of medical books from the Tang Dynasty onwards. Hence, apart from citing classics, no other sources are adopted. Occasional coincidences with other texts are merely accidental similarities, not plagiarism. Discerning readers will understand.
3. The book categorizes topics clearly. Even those unfamiliar with medicine can understand it when consulting it temporarily. It is the most convenient book for general use.
4. The discussions in this book stem largely from personal insight, but their innovations are based on facts and principles, supported by evidence and verification. Some are extended from ancient sages, while others are derived from Western medical methods. These are credible and verifiable claims, not fabrications.
5. This book focuses exclusively on Blood Disease, differing from miscellaneous diseases. Please do not apply examples from other conditions to this context, nor criticize this book using standards from other conditions.