6 CHEMICAL MAXUEES. 



makes 30 tons of that acid per hectare or 12 tons per acre. The 

 ditfiision of phosphoric acid in arable land responds, moreover, to a 

 providential law, that element being as indispensable to plant life 

 as to animal life. In the absence of phosphoric acid, none of our 

 cultivated plants can pass through all the phases of vegetation ; the 

 seed may germinate, produce leaves, stem, branches, but these 

 organs remain attenuated, lingering, till the plant dies prematurely 

 without bearino; flowers or fruit. Co ren winder made researches to 

 follow up phosphorus in plants. Analyses of roots, stem, and fruit 

 proved that phosphorus exists in nascent organs w^here it contri- 

 butes to organization. It diminishes proportionally in the root ; 

 thus the root of beet-root does not contain phosphorus after the 

 maturity of the seed. It is to be found in the seed. Corenwinder 

 found that in the pollen of flowers there is a considerable amount 

 of organic phosphorus recovered as phosphoric acid in the ash 

 of these minute organisms. In this respect pollen is analogous 

 with the seminal fluid. Saussure and, later, Garreau, Professor 

 of Botany at Lille, pointed out that the leaves of a tree give, on 

 estivation, ashes more rich in phosphorus than at any other epoch 

 of vegetation. If now we gradually ascend to the examination of 

 animals, we find that their bones, their muscles, their nervous and 

 cerebral substance, the fluids of their organism, blood, milk, 

 urine, seminal fluid, are always and everywhere permeated with 

 phosphorus. Intimately associated with organic substances, phos- 

 phorus abounds in the cerebral mass and the nervous system. One 

 may almost say that it is organized. Combined with oxygen and 

 lime it forms one of the important elements of the skeleton. Dis- 

 solved by the animal fluids, it is unceasingly carried from one point 

 to the other of the individual, and if its total amount remains fixed, 

 for a given animal, its molecule nevertheless displaced by solvent 

 or vital actions is excreted, then replaced by a new molecule, 

 brought by the digestive system. To remove phosphoric acid and 

 lime from the diet and try to nourish an animal on purely nitrogen- 

 ous principles is to attempt its life. The animal in this respect 

 behaves like the plant (Bobierre). Thousands of analyses made 

 of recent years by Thezard show that, amongst invalids, the elimina- 

 tion of phosphoric acid through the urine follows a progress parallel 

 with that of the disease. The further the latter progresses the 

 more does the phosphate content of the urine increase ; in these 

 conditions vrhen the loss resulting from the elimination cannot be 

 repaired by a diet appropriate to the needs of the individual, which 

 has led to phosphoric acid being regarded as the vital element j^o^f 

 excellence, the human organism perishes with frightful rapidity. 

 According to Elie de Beaumont, a human skeleton weighs, on 

 an average, 4*6 kg., say 10 lb., and assuming that human bones 

 contain 53 -04 per cent of phosphate of lime, a skeleton ought to con- 



