At The Sight Of A Single Bone,

Since Nothing Can Exist That Does Not Fulfil The Conditions Which Render Its Existence Possible, The Different Parts Each Being Must Be Co-ordinated In Such A Way As To Render Possible The Existence Of The Being As A Whole, Not Only In Itself, But Also In Its Relations With Other Beings, And The Analysis Of These Conditions Often Leads To General Laws Which Are As Certain As Those Which Are Derived From Calculation Or From Experiment.

Thus It Cannot Be Denied That The Masses Which Today Form Our Highest Mountains Were Originally In A Liquid State; For A Long Time They Were Covered By Waters Which Did Not Sustain Any Life.

Moreover, It Thus Follows That Not A Great Deal Of Time Was Needed For The Large Animals Of The Three Major Parts Of The World To Become Known To The People Who Spent Time On The Coasts Of Those Regions.

It Is In This Mutual Dependence Of The Functions And The Aid Which They Reciprocally Lend One Another That Are Founded The Laws Which Determine The Relations Of Their Organs And Which Possess A Necessity Equal To That Of Metaphysical Or Mathematical Laws, Since It Is Evident That The Seemly Harmony Between Organs Which Interact Is A Necessary Condition Of Existence Of The Creature To Which They Belong And That If One Of These Functions Were Modified In A Manner Incompatible With The Modifications Of The Others The Creature Could No Longer Continue To Exist.

Secondly, The Nature Of The Revolutions Which Have Altered The Surface Of The Earth Must Have Had A More Decisive Effect On The Terrestrial Quadrupeds Than On The Marine Animals.