It's about one-forty-thousandth as heavy as a Cow.
In other words, the weight of a Cow is 40,000 times 266.580 grains.(for Holstein, a.k.a. Holstein Friesian, a.k.a. Friesian, Bos primigenius) (adult, heifer)
A mature Holstein cow (the well-known black-and-white, spotted breed of cow) typically weighs 10,000,000 grains. President William Howard Taft (1909 - 1913) kept a Holstein cow named Pauline Wayne on the White House grounds — a gift from a Wisconsin senator and the source of the First Family's milk.
It's about 60,000 times as heavy as a Poppy Seed.
In other words, 266.580 grains is 58,000 times the weight of a Poppy Seed, and the weight of a Poppy Seed is 0.0000170 times that amount.(Papaver somniferum)
Fifty percent oil by weight, a poppy seed weighs approximately 0.0046 grains. The true pigment of a poppy seed is brown in color, while the characteristic bluish color is an optical illusion caused by a layer of calcium oxalate crystals refracting light rays.
It's about one-ninety-five-thousandth as heavy as a Car.
In other words, 266.580 grains is 0.000010460 times the weight of a Car, and the weight of a Car is 95,600 times that amount.(for 2009 Ford Taurus; automatic transmission; curb weight)
A 2009 Ford Taurus weighs 25,490,000 grains. The first mass-produced car, the Curved Dash Oldsmobile — introduced in 1901 — weighed just 5,957,000 grains.
It's about one-one-hundred-thousandth as heavy as a Giraffe.
In other words, 266.580 grains is 0.000008950 times the weight of a Giraffe, and the weight of a Giraffe is 112,000 times that amount.(Giraffa camelopardalis reticulata) (adult, male, maximum of range)
An adult, male giraffe can weigh up to 29,800,000 grains. Reaching 5.5 m (18 ft) in height by adulthood, giraffe calves can grow as much as 3 cm (1 in) per day.
It's about one-one-hundred-thousandth as heavy as a Rhinoceros.
In other words, 266.580 grains is 0.00000820 times the weight of a Rhinoceros, and the weight of a Rhinoceros is 120,000 times that amount.(for Black rhinoceros, Diceros bicornis) (Adult, male)
An adult black rhinoceros weighs between 32,000,000 grains. Rhinoceros are extremely aggressive — nearly one of every two males will die as a result of fighting with other rhinoceros.
It's about one-one-hundred-fifty-thousandth as heavy as The Tongue of a Blue Whale.
In other words, the weight of The Tongue of a Blue Whale is 160,000 times 266.580 grains.(Balaenoptera musculus) (adult)
The tongue of a Blue Whale can weigh up to 42,000,000 grains. Despite their tremendous size, blue whales feed almost exclusively on tiny crustaceans called krill and cannot swallow anything much larger than a beach ball.
It's about one-two-hundred-thousandth as heavy as a Hippopotamus.
In other words, 266.580 grains is 0.000004610 times the weight of a Hippopotamus, and the weight of a Hippopotamus is 217,000 times that amount.(Hippopotamus amphibius) (adult, male)
The average weight of an adult male hippopotamus ranges from 57,900,000 grains. Appearances to the contrary, adult hippos cannot swim or float in water; they actually move by leaping and walking across lake bottoms at about 8 kph (5 mph).