Mack Trucks, Inc. was formerly known as Mack Brothers Motor Car Company (1900 - 1911). It became known as the International Motor Truck Company (1911 - 1922) when it purchased the Saurer Motor Truck Company. Mack Trucks, Inc. became the official name in 1922. Today Mack is a subsidiary of AB Volvo (since 2000).

This looks like a Mack Model AB, built by the International Motor Truck Company, starting in 1914, as shown in the pictures below. All early AB trucks could be ordered with either worm or chain drive. The AB model was produced through 1937 (with coninuous modifications, of course), and over 55,000 were made during this timeframe. One of those changes was a much larger radiator starting in 1923, so this truck is from 1922 at the latest.

The bulldog logo was first introduced in 1921 and it was made the offical corporate logo in 1922. The bulldog hood ornament was first introduced in 1932.

Those kids look like they are having the times of their lives. The driver even let a few up to the front to play with the wheel.

The Mack AC line of chain-driven trucks was nicknamed "Bulldog" by British engineers. Bulldog trucks eventually let to the English Bulldog logo in use to this day. This vintage vehicle had solid rubber tires.

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A late-teens truck listed as a Mack (International Motor Co.). Must have been before there were bulldogs! Doubt that Mack built the actual bus, but a truck body company probably used their chassis.

I think Anonymous Tipster is correct. Mack made trucks under the International Motor Company name in the 1910s. I think that logo is an "I" and "M" together. The bulldog as the corporate logo wasn't used until later. 1922 I think.

Logo on the radiator cap looks similar to this.

A late-teens truck listed as a Mack (International Motor Co.). Must have been before there were bulldogs! Doubt that Mack built the actual bus, but a truck body company probably used their chassis.

Early vehicles used carbide lamps, similar to those used in mines, which generated acetylene by reacting calcium carbide with water, while later vehicles carried canisters of acetylene dissolved in acetone that saturated a filler material, and the gas was piped to the lamps. I'm not that familiar with auto lamps, but to me the pictured lamp doesn't resemble either of those above, and may in fact burn kerosene.

I have never seen a bus like this one. It seems to have no headlights except what appears to be a lantern on the driver side. I can see the horn sticking through the cowl below the windshield. What kind of bus is this?