The food that you take consists of nitrogenous elements and proteins, fats or hydrocarbons such as ghee, and carbohydrates such as rice and sugar. Proteins build up the tissues and the muscles. Carbohydrates produce energy. Besides these, there are various kinds of salts also. The various digestive juices, saliva in the mouth, gastric juice in the stomach, bile, pancreatic juice and the Succusentericus or the intestinal juice in the intestines act upon the particles of food during their passage in the alimentary canal or digestive tube. Saliva acts upon starch. It converts it into sugar. This action is further taken by pancreatic and intestinal juice, in the intestines. Bile acts upon fats. Gastric juice and pancreatic juice act upon proteins. The whole thing is converted into a milky juice called chyle. This chyle is absorbed by lacteal vessels and it is mixed with blood. The right side of the heart contains impure blood. This impure blood is sent to the lungs for purification and after being purified is brought back to the left side of the heart, and from there it is pumped through the big artery aorta, throughout the body. In the capillaries the blood exudes as lymph and bathes and nourishes the tissues and cells of the body, and the impure blood is carried back by veins to the right side of the heart.
The waste products of food are carried along the large intestine which is six feet in length to the rectum where it is retained as faecal matter. When the nervous impulse is carried to the rectum from the defecation centre in the spinal cord, it is discharged through the anus, the terminal opening of the alimentary canal.
The kidneys, that are situated in the loins, on each side, eliminate the urine from the blood and send it through two tubes called the ureters to the reservoir of urine called 'bladder'. From the bladder it is discharged through the urethra.
The nervous system consists of cerebrum of fore-brain, cerebellum or hind brain, spinal cord and the sympathetic nerves. There are various centres in the brain for hearing, seeing, tasting, smelling, speaking, etc. The different impulses from the hands, when a finger is stung by a scorpion, are carried through the sensory nerves to the spinal cord and from the spinal cord to the brain. Mind, that has taken its seat in the brain, reacts. It feels. An impulse travels from the spinal cord and thence along the motor nerves to the hand. At once the hand is taken back from the scorpion. This is all done in the twinkling of an eye. The sympathetic nerves supply the internal organs of the abdomen, liver, spleen, heart, etc.
Now I will describe how this vital fluid semen is manufactured. The two testes or seeds that are located in the scrotal bag are called secretory glands. These cells of the testes have been endowed with the peculiar property of securing semen drop by drop from the blood, just as the bees collect honey in the honeycomb. Then this fluid is taken by the two spermatic ducts or tubes to the two small bags or reservoirs for the semen called Vesiculae Seminalis (seminal bags), one on each side. Under excitement it is thrown out by small ducts called ejaculatory ducts into the portic portion of urethra or urinary canal, where it is mixed with the prostatic juice, secreted by the prostate glands. Who is the real Director of these internal organs? Who has created this subtle, internal, magnanimous machinery? Are you not struck with awe and wonder, my dear friends, when you think for a moment seriously about the Divine Grandeur and Divine Glory, that are exhibited in the structure of these miraculous mechanisms, heart, lungs, brain, etc.? How harmoniously do they work! Who converts food into blood? Who pumps the blood into the arteries? It is He. Feel His indwelling presence. Pay your silent homage to Him. Glory, Glory, unto the Lord, the Creator of this wonderful body, His own image, His own dwelling house, the Navadvarapuri, the nine-gated city!
