What is the significance of the City of Chicago Incorporation Seal with the Native American etc?

this is an offical explnaing of the seal from an old Chicago Police Handout form then 1970's

The Americain Shield is for the national spirt of Chicago.

The Native Americain Chief is for the discoverier of the site of Chicago and the contribution to the early history of Chicago

The Ship is emblematic of the approch of the "white man's" civilation and commerce

The shaft of Wheat is the symbol of activity and plenty

the infant child in the Shel is a classical symbol of the pearl with Chicago being on the shore of the lake signfies that Chicago shall be the "Gem of the Lakes" then child also represents the first white child born in Chicago in 1805.

the motto "urb in horto" means city in a garden

and march 4th 1837 is when Chicago was incorperated as a city