After you look at these images of meat-packing facilities from early last century, you'll understand why social reformer Upton Sinclair wrote his great 1906 novel The Jungle about workers' horrific experiences in the meat packing industry.

The mince meat department in Armour's great packing house, Chicago, c. 1893

Utterly Disturbing, Century-Old Photos of Meat-Packing Facilities

(via Library of Congress)

A Half Mile of Pork, at Armour's Great Packing House in Chicago, around 1894

Utterly Disturbing, Century-Old Photos of Meat-Packing Facilities

(via Library of Congress)

Workers

Utterly Disturbing, Century-Old Photos of Meat-Packing Facilities

(via Ralphmag)

The old Union Stockyards in Chicago, early 1900s

Utterly Disturbing, Century-Old Photos of Meat-Packing Facilities

(via Site Design)

Cutting up hogs in Swift & Co.'s Packing House, c. 1905

Utterly Disturbing, Century-Old Photos of Meat-Packing Facilities

(via Library of Congress)

Making link sausages with machines that could stuff 10 ft. per second, c. 1905

Utterly Disturbing, Century-Old Photos of Meat-Packing Facilities

(via Library of Congress)

Washing and tagging freshly killed lamb, 1906

Utterly Disturbing, Century-Old Photos of Meat-Packing Facilities

(via Library of Congress)

Knocking cattle before slaughtering, 1906

Utterly Disturbing, Century-Old Photos of Meat-Packing Facilities

(via Library of Congress)

A slaughterhouse in Canada, around 1907

Utterly Disturbing, Century-Old Photos of Meat-Packing Facilities

(via Library and Archives Canada)

Cutting up meat in a German packing house

Utterly Disturbing, Century-Old Photos of Meat-Packing Facilities

(via Library of Congress)

Packing sliced bacon in glass jars, c. 1909

Utterly Disturbing, Century-Old Photos of Meat-Packing Facilities

(via Library of Congress)

As a lamb to the slaughter, photo by George Boston Brayton, c. 1913

Utterly Disturbing, Century-Old Photos of Meat-Packing Facilities

(via Library of Congress)

Chicago meatpacking plant workers, 1905

Utterly Disturbing, Century-Old Photos of Meat-Packing Facilities

(via Thomson Wadsworth)

Pen of hogs at William Davies Company, a photo by William James Topley, 1920s

Utterly Disturbing, Century-Old Photos of Meat-Packing Facilities

(via Library and Archives Canada)

A butcher inspects a rack of hams, c. 1928

Utterly Disturbing, Century-Old Photos of Meat-Packing Facilities

(Photo by Three Lions/Getty Images)

Cattle are first led into a narrow alley and stunned by a blow on the head, in a packing plant in Austin, Minnesota, 1941

Utterly Disturbing, Century-Old Photos of Meat-Packing Facilities

(via Library of Congress)

Heads of beef cattle, Austin, Minnesota, 1941

Utterly Disturbing, Century-Old Photos of Meat-Packing Facilities

(via Library of Congress)