A year later, a well-known German physician, Dr. Ebstein[312] published a very careful treatise on the same subject. He had been struck by the fact that among those who have reached a great age, there have been several who had led an exuberant life, full of excesses, notably in the consumption of alcohol. None the less, Ebstein advised either a complete avoidance of alcoholic liquor, or at the most an extreme temperance in the use of it. He prescribed in addition the simplification of the conduct of life and the avoiding of anything that is unwholesome. Study of such works, which are written in a scientific spirit, convinces me that a science of the prolongation of life could be built up. An exact investigation of the phenomena of old age would contribute to this object. At any rate, we cannot set aside as chimerical plans to make old age a natural process, and one easy to bear. I believe, moreover, that attempts to prolong life deserve to be encouraged, the more so as instances of longevity are already numerous. Quite a number of cases of centenarians who have preserved intellect and vigour until death have been recorded. It is unnecessary to relate the histories of these persons, of whom some attained such ages as 120, 140, and even 185 years (Saint Mungo of Glasgow). My friend, Professor Ray Lankester,[313] thinks that such unusually old persons are monstrosities comparable with those who have attained a gigantic stature. But centenarians are more numerous than giants, and while the latter exhibit marked signs of pathological weakness the former surprise us by their health and vigour. The longevity of the Israelites recorded in the Old Testament is well known. No doubt there is much exaggeration in these naïve records. Was it an error of exaggeration to impute an age of 969 years to Methusaleh, or of 595 to Noah, or were these ages reckoned on a different basis? Henseler[314] suggested that in these cases each season was counted as a year, so that the age of Methusaleh was really only 242 years, a length of life not so vastly greater than ages recorded in modern times. There is evidence to show that in somewhat later Biblical times ages were reckoned in our years. Thus in the Book of Numbers (i. 3, 20, 22) reference is made to those “From twenty years old and upward, all that are able to go forth to war in Israel.” The limit of age given shows clearly that the years counted were our years. This interpretation is supported by many other passages in the Pentateuch, notably where annual harvest feasts are spoken of. We may therefore accept as probable the assignment of such ages as 100 or 120 years to several Biblical personages, such as Aaron, Moses, and Joshua. And the words put in the mouth of Jahveh may be accepted as important evidence: “And the Lord said, My spirit shall not always strive with man, for that he also is flesh: yet his days shall be an hundred and twenty years.”[315]