"Canals": What appears as canals through our Jasoomian telescopes are actually fertile, irrigated strips of farmland.  Water is collected in immense underground reservoirs at the poles from the melting ice caps.This water is pumped through long conduits to the various populated centers where it is distributed to farms and cities. Along either side of these conduits, and extending their entire length, lie the cultivated districts. They are divided into tracts of about equal size, each under the supervision of one or more government officers. Instead of flooding the surface of the fields, and thus wasting immense quantities by evaporation, the water is carried underground through a vast network of small pipes directly to the roots of the vegetation.

Underground transport links the Twin Cities of Helium which are 75 miles apart

Pneumatic tube transport systems are part of the rapid transit system between the Twin Cities. Passengers are propelled through the 75-mile tubes in eight-foot-long bullet-shaped cars.

Pits & passageways under cities

Ramps instead of stairs are used in all over Barsoom.

Home Security is achieved by using hydraulics to lift houses up at night for safety.

Door Locking Mechanisms are controlled by a series of light rays of varying intensity for specific lengths of time.

Surveillance cameras are used in Zodanga's Royal Palace

Directional lighting:  In Barsoomian street lighting, the light leaves the lamp, goes around in a circle, illuminates everything in its path and then returns to the lamp. SM

Torches of Horz are cylindrical portable lighting devices with a central core which glows when exposed to air. The secret technique of producing this central core has been lost for centuries.

Forandus is the hardest and lightest metal on Barsoom. It is commonly used in the making of wall panels.

Radium Light Bulbs are the principal means of artificial lighting on Mars. They are hemispherical glass bowls, filled with radium powder, which gives a clear but glareless light almost indefinitely. The bulb is never extinguished, but is fitted with an opaque cover when not in use.

Holographic Telescopes

Telescopic Cameras are capable of taking pictures of Earth objects as small as a blade of grass. PM11

Glass-Domes are used to cover whole cities in northern polar regions. Here, solar energy is trapped and stored in huge reservoirs.

Solar Energy used in northern cities for heating and a source of energy.

Concentrated energy food tablets

Food Automats prepare and serve food entirely by a mechanical apparatus. The diner selects the food to be served by pressing tiny buttons.

Healing powders and ointments of remarkable powers can heal wounds of any severity.

ID Rings WM

ID Machines are used in northern nation of Okar to measure, weigh and photograph people. Copies of this information  are reproduced instantly in offices all over the region.

Dance of Barsoom One-Stringed Instrument is an exotic instrument made of skeel (a Barsoomian hardwood) and shaped to fit the left forearm of the dancers. Characters are inscribed upon it denoting the pitch and length of its tone. There is also a ring wound with gut which is worn between the first and second joints of the index finger of the right hand and which, when passed over the string, elicits the single tone required of the dancer.

Invisibility Tablets are used by the invisible warriors of Invak and Onvak in the Forest of Lost Men. It renders them invisible except under special artificial lighting in their cities. A tablet takes effect after an hour and lasts for one day.

Radio Technology: There is a great variety of radio-related equipment from large to miniature with various modes of transmission & reception,  secret frequencies, transmission codes, headsets, etc.

Nerve Index Machines control the bodies of people. This machine was invented by scientist Myr-lo for the Jeddak of Kamtol who holds all his subjects and slaves in absolute control. The machine is keyed to their nervous systems via shortwaves and enables him to kill all escapees or rebellious subjects with the simple pushing of a button.

Photostatic copiers which reproduce images in an instant are used in the Temple of Knowledge.

Computer Fax and Teletype Machines record and transmit data.

Gridley Wave is a type of radio wave discovered by Jason Gridley of Tarzana, California, and is also used by Barsoomian scientists. Ulysses Paxton transmitted the story of Tan Hadron of Hastor to Burroughs via this medium.

Sophisticated Chronometers

Longitudinal Positions (Central Meridian) are reckoned from the ancient city of Exum.

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Through Ras Thavas of Toonol, the Mastermind of Mars, ERB presented a long string of innovations long before they appeared on Earth:

Transplanting of Organs through sophisticated surgical techniques
Brain Transfer
Restoring of Severed Limbs
Iron Lungs
Artificial Hearts
Multi-Focal Lenses in eye glasses
Sophisticated Hearing Aids
Intricate Brain Surgery
Instruments to study thought waves of inhabitants of distant planets
Freezing and Reviving of Bodies, i.e. suspended animation,
Homads - synthetic men
Malagors - a recreation of extinct huge flying birds on which the Homads rode
Television