Some readers questioned the situation of the Thomson submachine gun in Ding Yi's novel, and the information is now published as follows:

The Thompson submachine gun was named after the American General Thompson, but it was actually designed by the Americans O. V. Perth and T. H. Oakkhoff. Also known as the Chicago printer.

The early development product of the submachine gun was the M1919 type, its earliest production model was the M1921 type, and later the M1923 and M1928 series submachine guns appeared one after another. Among them, the M1928A1 type was successfully developed in 1930, and a small amount of equipment was used by the US army, and was also used by the armies of Britain, France and other allied countries in World War II.

In 1942, the M1928A1 was improved, the M1 submachine gun was developed, and it was officially equipped with the US army, becoming the first standard submachine gun of the US army, and later improved to the M1A1 submachine gun on the basis of the M1.

During World War II, more than 1.4 million Thompson submachine guns were produced, which ceased production in 1945 and were gradually replaced by the American M3A1 submachine guns.

Compared to other 9mm submachine guns, the .45 caliber Thompson submachine gun was heavier and more difficult to aim, but despite this, the Thompson was still one of the most powerful and reliable submachine guns.

As for when the Thomson submachine gun entered China? There are examples.

As early as that year, when Mr. Sun Yat-sen attended the opening ceremony of the Whampoa Military Academy, the guards behind him carried a large, front and rear grip, with a drum on their shoulders, it was equipped in China for nearly 60 years, and it was more widely used and more famous than the "flower machine" - MP18/28 submachine gun that entered China at the same time. Thomson's original English text is ThomPson, and due to different translations, it is also translated as Thomson, Thompson or Thompson in China. In China, this weapon is often referred to as the "Tomson hand-held machine gun", which is simplified to "Tom gun" or "Tom style".

The "Tom type" is also one of the earliest imitation submachine guns in China. From 1923 to 1924, the Guangdong Arsenal copied 39 M1921s. In 1926, the Shanxi Military Craft Training Factory also began to imitate, and in 1927, after being renamed the Taiyuan Arsenal, a submachine gun factory was specially established, with a monthly output of 900 in 1928. After the takeover by the Nationalist Government, production was suspended for a time, and production resumed between 1932 and 1934, with a maximum monthly output of 250 pieces. By 1946, the Northwest Manufactory was again mass-producing the gun. These imitations are collectively known as the "Jin-made hand-held machine guns", and can be divided into two models according to whether there is a small grip in front of them, the one with a foregrip is longer and heavier, and both use a 20-round magazine, and can also be used for a 50-round drum. These "Tom-style" models are all nominally 11.25 mm in caliber, which often leads people to mistakenly believe that they are different from those of American origin, when in fact the ammunition of the two is universal. Another major manufacturer of the domestic "Tom type" was the Chongqing Weapons Repair Institute, which produced a total of 4,700 pieces of two models between 1928 and 1935, both with a caliber of 7.63 mm, in order to be compatible with shell gun cartridges, one of which was imitated from the M1923 model, equipped with a bipod, which could double as a light machine gun. In addition, Huayin, Chishui and other arsenals have also imitated this gun. The extent of these domestically produced Thomson imitation equipment is far beyond today's imagination, and it was used by warlords from all walks of life in the Central Plains War, and before the Anti-Japanese War, even the armed forces of ethnic minorities in the Ganliang area had a small number of Thomson submachine guns. Compared with the original American guns, these imitations are different in size and details, the parts are generally not universal, and the quality is even more uneven, and because of wear and tear and the source of bullets, they are not used much after the middle of the Anti-Japanese War, and are replaced by the original products provided by the United States. Due to the large number of imported products, although in 1947 the 90th Arsenal of the Kuomintang also successfully copied the "four or five submachine guns" based on the M1 type, but in the end it was not mass-produced. Already during the First Civil Revolutionary War, the Red Army began to come into contact with and use the "Tom-type" submachine guns, most of which were domestic imitations. In the early days of the Anti-Japanese War, the Eighth Route Army was also equipped with a small number of Jin-made submachine guns.

(Note: The above information is taken from a number of online articles and blogs, due to publication reasons, the sources cannot be listed one by one, sorry.) ）