Patterns of water, ash and organic-matter changes in senescence

A study of the changes in moisture, ash and organic matter in the organs of rats and mice has provided good evidence that there is a continuance of processes that occur at a constant rate throughout life. This rate is more rapid in the very early period of life, but the changes are related constantly to each other, as well described by certain mathematical equations. The loss of moisture is an hyperbolic function described by the logarithm of the percentage of concentration varying directly with the logarithm of the age of the animal. Similarly the concentration of ash declines while the total weight, total water and total ash increases by a complex exponential function described by a logarithm of the age in weeks. The gain in organic matter is best described by a power equation in which the logarithm of the percentage of organic matter is directly proportional to the logarithm of the age in weeks. These findings are in keeping with our previous suggestions and findings that constants of senile decay can be mathematically derived. It is further concluded that senility does not have a sudden onset, but is an accumulation of constantly related phenomena that can be accurately described mathematically.