The Colt House Revolver (also called, in its alternate 4-round capacity model, the Cloverleaf) was one of the first metallic cartridge rear-loading revolvers to be produced by the Colt's Patent Fire Arms Manufacturing Company, in 1871.
The same year, Colt's also patented the Colt Open Top, another metallic cartridge rear-loader, but in fact the Open Top production didn't start until 1872, although a pocket version of the Open Top, a completely different design, went on sales as of 1871, the Colt Open Top Pocket Model Revolver.
[2] Both models, House and Cloverleaf, were built around a solid hidden spur-trigger frame, a weapon architecture also used by another Colt gun, the Colt Sidehammer (1855).
[3] Finally, both models, House and Cloverleaf, were chambered with .41 caliber rimfire cartridges, available in both long and short sizes.
The main differences between the two models were the following:[1] The Colt New Line (1873) inherited the general shape of the Colt House: a bird's head grip and a solid spur-trigger frame.