Stable-mates Lewis and Harris are named after neighbouring islands in the Western Isles.
Harris, whose name was chosen by the public in an online vote last week, has been joined this week at Police Scotland's mounted unit by Lewis.
The force described Lewis as "lovely and quiet" and also its smallest horse at about 16.2 hands high.

Sylvia Blackburn, 72, suffered serious head injuries outside Bedford Road Lower School, Kempston, on 19 December 2014.
Luton Crown Court heard Brian Wright, 55, of Kempston, said he was unable to see at the point of impact.
He denies causing serious injury by dangerous driving.
Prosecutor Sally Mealing-McLeod said Mrs Blackburn, a lollipop lady for 20 years, had been on duty in Bedford Road as pupils were leaving school on the last day of term.
She was wearing a long-sleeved high-visibility orange and yellow coat which had reflective strips and "school crossing patrol" written on the back.
When the traffic lights turned red, she stepped out to escort a woman and her six-year-old daughter across the road.
Traffic travelling in the opposite direction stopped, but Mr Wright's VW Golf failed to stop and hit her at 14mph, the jury heard.
Witnesses described Mrs Blackburn's head hitting the screen pillar of the windscreen before she struck the wing mirror and then the road.
The married mother of three was airlifted to Addenbrooke's Hospital in Cambridge.
She was later transferred to Bedford Hospital and is now at a residential care home for people with an acquired brain injury.
Mr Wright, of The Dell, declined to comment in police interview but in a statement said he was blinded by the setting sun and lowered his visor but was unable to see when the collision happened.
The court heard the sun was 10 minutes from setting and could have been shining into Mr Wright's eyes.
Ms Mealing-McLeod told the jury that if his vision had been affected he should have stopped.
The trial continues.

Steven Rodriguez, who was better known as A$AP Yams or Yamborghini, died aged 26 on 18 January at Brooklyn's Woodhull Medical Centre.
He founded the US rap collective A$AP Mob along with fellow New Yorkers A$AP Bari and A$AP Illz.
Now the New York Times reports that his death was caused by acute mixed drug intoxication.
Opiates and benzodiazepines were found in his system and it was ruled an accident.
After his death artists paid tribute to him on social media.
Drake tweeted: "Rest in peace Yams. A$AP is family."
Azealia Banks wrote: "ASAP YAMS should be remembered as a leader, an innovator and most importantly as an important part of NYC youth culture."
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Towns and cities along the Baltic coast were flooded, from Kiel in the far north to the resort island of Usedom near the Polish border.
Sea levels were recorded in the port of Wismar at 1.83m (6ft) above normal overnight.
Severe winter conditions also hit Sweden and Finland.
The overnight temperature fell to -41.7C at Muonio in Finnish Lapland, near the north-western border with Sweden, the coldest night of the winter so far.
Further west in northern Sweden, temperatures fell as low as -41.3C and road conditions were treacherous in much of the country.
A passenger train became stuck without power and heating for several hours in the north-eastern Norrbotten region with outdoor temperatures at -38C. Swedish media said no replacement buses were prepared to venture out because of the cold.
Some of the worst flooding in northern German was in the historic centre of Rostock and in Stralsund, as well as on Usedom, where major damage was reported. Outdoor staircases were washed away and snack bars badly affected.
"This is no children's tea party," said one local official. However, water levels were expected to fall in the coming hours.
Storm Axel was also responsible for the arrival of several hundred thousand plastic eggs on the island of Langeoog on Thursday.
Local reports said the eggs contained little toys with Russian messages inside and appeared to have come from a container that had fallen off a ship.
Scotland's newest police horses have been named after two of the country's most famous islands.
[NEXT_CONCEPT]
A driver "blinded" by the sun drove through a red light at a pedestrian crossing and knocked down a lollipop lady, a jury has heard.
[NEXT_CONCEPT]
American rapper A$AP Yams died of an accidental drug overdose, according to New York City's chief medical examiner.
[NEXT_CONCEPT]
A storm surge has caused the worst flooding on Germany's north-east coast since 2006, leaving streets and cars submerged and causing major damage.