Circuit of the Blood. --the blood thus purified passes back to the heart to go on its circuit through the body, every organ of which renews its energy and vigor from the Magician's fiery wand, pure, healthy blood; while the air exhaled carries off the impurities.

Change in color of blood. --during this process the blood changes from a dark purple to a bright red. Pure air is the cheapest necessity and the greatest luxury of life. Let it not be the rarest. The relative proportion of the respirations to the pulsations of the heart is about 1 to 4 1/2 or 5; and the quantity of air required to keep the blood pure is very great. Indeed, respiration is the falling weight, event spring, which keeps the clock of life in motion; the inspirations and expirations are the strokes of the pendulum which regulate it.

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I have a new theory. Actually maybe this is my first theory. I think the authors may delve into flowery language and the peculiar like analogies whenever they don't know what they're talking about. I could be wrong I like to give the authors the benefit of the doubt. However it seems that whenever they lacked substance and factor knowledge, their prose gets a little loose.

I've also heard that it is a urban legend today that blood has two different colors. If that is truly an urban legend and blood does not have the color of purple and red, and this book might actually be one of possibly many sources that helped to create that legend, which may not be all that urban after all. Maybe more of a historical legend.

Wikipedia today provides an excellent description of what the color of blood is and why it is that color.  They describe a situation of optical illusions that led scientists and doctors as evidenced by the Library of Health to believe that veinous blood deprived of its oxygen was actually 'purple' or blue.  Sheesh

Additional Articles from the Book of Medicine:

• A Case of Impure Ice Poison
  
  

  A Case of Impure Ice Poison.  — such was notably the case in an epidemic of intestinal disorder which occurred at the watering place of Rye Beach N. H.  from the account of Dr. Nichols, who attended most of the patients, it seems that, early in the season, a mild form of disturbance of the stomach and bowels made its appearance among the guests of a particular hotel at his favorite summer resort.  The symptoms were in general penis, nausea or vomiting, diarrhea and severe abdominal pain, accompanied by fever, loss of appetite and mental depression.  The well and drainage system of the establishment, which had recently been put in complete water, was found almost faultless, and the milk supply of unquestionable purity; but on the attention of the physician being directed to the stock of ice provided for the guests, conclusive proof of its dangers quality was promptly obtained.

• Muscles of the Shoulder
  
  

  The large triangular muscle of the shoulder — the deltoid — is one of great strength, as in fact are all the muscles of the arm.  If you grasp the arm tightly just above the elbow joint, and then bend the forearm, you will feel the biceps muscle of the arm become firm, hard and prominent; now straighten it again and it becomes relaxed, whilst the muscles on the back of the arm become hard and prominent. The muscles of the forearm are the flexors and pronators; that is, they flex the arm and turn the palm downward.  In each upper extremity or arm there are fifty-three muscles, and we observe here the nicest and most economical method of packing away the muscles that could be improvised, securing strength, giving elegance to its form and shape and facilitating its mobility.

• Diarrhea and Dysentery from Impure Water
  
  

  Diarrhea and Dysentery from Impure Water.  — the instances of outbreaks of these two diseases from contaminated water supply are very numerous, and probably most persons can recall examples of this kind.  The impurities which produce diarrhea and dysentery are suspended earthy matters, such as are found in most river waters after a rain; suspended animal and vegetable material; salty thing chlorides of Lyme and Magnesia, and nitrate of ammonia and of lime.  Besides the numerous outbreaks traceable to direct sewage contamination, there are several instances recorded of indirect poisoning the water supply from this source, as in the following curious case.

  Just as a note about the style of writing or documentation, this paragraph seems to be unnecessary as a stand alone topic.  Instead it is basically a transition paragraph, yet the author chooses to use it as a stand alone sub topic instead of just using it to work his way from one topic to a very slight tangent in the next topic.  This would again seem to reflect the author’s possible motivation for not only being paid by the word but also with a stipend for important bolded topics.  This surely does not seem to be practical like following a guide on replacing coilovers in a car or fixing a plumbing problem, and it must have driven some readers nuts as they used this book in semi-emergencies looking for the answer to serious problems only to be distracted by useless sections like this.