John H. B. Latrobe's patented heating stove - Latrobe Stove - 1846

The Latrobe Stove was so popular that The Century Dictionary listed "latrobe" as a generic label for all similarly designed stoves. It "arranged for heating floors above by means of a hot-air flue fitted with a damper and register."  The Latrobe Stove was also called Baltimore Heater, Parlor stove or Fire-place Stove and initially made by the Latrobe Stove foundry.  JHB Latrobe was a multi-talented man - B&O railroad lawyer, inventor, helped found and led organizations such as the Maryland Historical Society, and more HERE .  He thought about the problem after hearing "a complaint made by his wife, that the stoves then used (the "Franklin" and others) occupied so much space. He said he could remedy this, and would make a stove to be placed in the fireplace."


"On the 5th of September, 1846, John H. B. Latrobe, Esq., of Baltimore, obtained a patent for a stove which is now generally called "The Latrobe Stove," "The Baltimore Heater," or "The Fire-place Stove," etc. It is a fire-place stove, and the principle of its action in warming the rooms in the upper stories is so generally understood here, that any further description of it is thought unnecessary. There are now many patents connected with it. It is in large demand, and a great majority of the new houses, less than twenty-five feet front, are supplied with them, and almost entirely warmed by them. Of the 180,000 dwellings supposed to be under consideration, it may safely be assumed that the fire-place heater is used for warming at least one-sixth of them, viz., over 30,000. Thus it supplies the comfort of warmth to 150,000 persons, for whose benefit this paper is designed. It is, therefore, worthy of especial remark.

This stove is economical, convenient, always under observation, attractive, and highly popular. It warms the room in which it is set by radiation, and those above by "convection."

House and Senate Documents Maryland General Assembly  1884

From:  John H. B. Latrobe and His Times, 1803-1891 by John E. Semmes.  Baltimore: 1917 -

"In 1846 there was granted to John H. B. Latrobe a patent for improvement in stoves. This was the celebrated fireplace heater. Mr. Latrobe rather refrained from taking to himself any credit for this very useful invention, as not being in accord with his professional life. As he states in his memoranda, the case of Wilson v. Rosseau, already referred to, gave him a reputation in what was known as patent law, and he was engaged in many cases involving the validity of patents. He remarks that he is afraid that this has injured the reputation which he had at one time of being a sound lawyer. Still he says, "I have no reason to resent this for the returns in this description of practice are good, and I have had my share of it, and have now too short a time to practice anything new, or attempt to change, even if I desired it."

Feeling as he did about patent law, and that its practice was, to a certain extent, injurious to his reputation as a sound lawyer, he shrank from being known as the inventor of a stove, believing that his professional reputation would no doubt cease, and that he would be known only as a maker of stoves. We all have our weaknesses and this was one of Mr. Latrobe's.

He told me once that the way he came to be interested in the question was through a complaint made by his wife, that the stoves then used (the "Franklin" and others) occupied so much space. He said he could remedy this, and would make a stove to be placed in the fireplace. This was the beginning of the fireplace heater, a copy of the design of which is here shown. The stove serves both as a stove and a furnace; the hot air above the stove being collected and carried by flues to the rooms above.

Franklin (Benjamin) was the inventor of the stove known as the "Franklin," so that, as an inventor of stoves, Mr. Latrobe was in good company. The fireplace heater became very popular in Baltimore. At one time there were in use about 300,000. Mr. Latrobe once said to me, if his pride had permitted him to do so, he could have realized more money from this invention than he did from the practice of law."

The Latrobe stove Foundry was bought in 1846 by Hayward and Company (originally formed in 1837 as Hayward and Friend, then Thomas Bartlett joined the brothers, eventually name changed to Bartlett-Hayward & Co.
Latrobe, Ferdinand Claiborne. Iron Men and Their Dogs.  Baltimore: 1941  225p

A History of Hayward And Friend, 1837-1840, Stovemakers.

PATENT  -  J.H.B. LATROBE.  Fire Place.  Sept. 5, 1846.  #4744A

Be it known that I, JOHN H. B. LATROBE, of the city of Baltimore and State of Maryland improvement in the Mode of Heating Rooms, and that the following is a full and exact description of my improvement.

I use a stove with radiators on each side of the receptacle for the fuel, which last may be either round or square, and which is commonly called the cylinder. This stove is the same in principle with that in common use for the burning of anthracite coal, and, as is well known, consists of a lower box or drum of sheet iron on which stands the cylinder, with a pair of columns, or an upright box or drum with a vertical division, on each side, the whole being connected at top by the upper box or drum which has also a vertical division in it parallel to the front. The fire being lighted in the cylinder the draft passes either directly up the chimney or by closing a valve, is made to descend the front columns or corresponding spaces, where side drums are used, and, passing through a connecting chamber in the lower drum, to ascend the back columns or spaces into the upper drum, and thence into the chimney-heating in its progress the contiguous surface of the stove. Upon the plan here described, which is well known, I construct a stove to fit into the ordinary fire place of the room it is desired to warm, leaving a space all around it; that is to say the lower drum is raised about two inches above the hearth. The upright drums are an inch and a half or two inches from the sides of the `fire place and parallel thereto, and the upper drum is the same distance below the opening of the fire place. The fronts of the upper, lower and side drums are yin the same plane, or cut out of the same sheet of iron, which projects all round so as to close in front the open space just described, by reaching to the hearth below and lapping over the opening of the fire place at the sides and top. The back of the lower and side drums are also in one plane, the sheet iron projecting at the bottom and sides so as to fit close to the' bot-tom and sides of the fireplaceback. (This is easily managed by a careful measurement in each case before making the stove, or flanges of iron may be fastened to the bottom and side drums to answer the same purpose. The throat of the chimney at a convenient distance up is closed with a sheet of iron made tight with a little mortar, and having a hole to admit the stove pipe with a close fit. An Opening in the bottom of the hearth under the center of the stove, admits the external air as hereafter described in the reference to the drawings.

It will be seen at once that the spaces between the lower drum and the hearth and the side drums and the sides of the fireplace form chambers or channels through which the external air, from the opening in the hearth passes into the space above the stove and from thence as it cannot escape in front into the room nor up the chimney, it passes down behind between the upper drum and back of the fireplace and through the interval between the cylinder and side drums out into the apartment as show by the red arrows. The channel or chamber thus formed between the stove and the bottom and sides of the fireplace for the passage of the external air, may also be formed by an outer casing of tin or sheet iron at the bottom, sides and top of the stove, which outer casing would be in contact with the bottom and sides of the fireplace, an opening being made in it corresponding with the opening in the hearth already described, but this is a variation in construction only, not affecting the principle of my invention. Thus while the stove visible from the room heats the latter by direct radiation, the parts concealed within the fireplace, heat the air which passes in contact with them, in the manner described so that it is warm when it enters the room.

It will be seen that the adaptation of a stove in the manner and for the purpose described to an ordinary fire-place from which it can be removed at pleasure without materially or perhaps at all disturbing the original structure is an important object gained by my improvement. Another is that the peculiar character of stove heat is changed by the current of fresh air constantly entering the room at an agreeable temperature. Besides, the unsightly appearance of an ordinary stove is avoided inasmuch as the stove used sets wholly within the fire place. When the back of the fire-place is perpendicular there is no need for any alteration to lit it for the stove, nor is any absolutely necessary when the upper part of the back leans forward, because the stove may the sake of increasing the fire surface and facility of construction, that the back be straightened before putting in the stove which may then be made without a slope.

The accompanying drawings and model are made a part of my specification and fully illustrate it.

What I claim as new and desire to secure by Letters Patent is -

The employment of a stove such as described, so constructed and  placed within the ordinary fire place as to heat the room by its direct radiation as well as by heating air entering the room from the outside as described, serving the double purpose of a stove and hot air furnace.

Explanation of drawings.

Figure 1, shows the front view of an ordinary replace, with the stove in its proper place. An isometrical top view of the stove is represented by the dotted lines. The dotted red lines show the opening of the fire-place which is hidden by the front casing of the stove. The dotted black lines show the top and side drums and the upright round smoke pipe leading into the chimney above. The heavy dotted blue lines behind the ashdrawer, show the opening in the hearth for the admission of pure atmospheric air.

Fig. 2, shows the plan of the top of the stove, supposing the top of the upper drum removed.

b b is the casing of the fireplace.

c the stove itself.

d, d, the descending pipes or chambers for the smoke.

e, e, the ascending pipes.

f, f, the chambers for the ascent of the atmospheric air between the fire-place and side-drums, divided by the partitions g, g from the space h, at the back of the stove, where the air from the outside descends and passes around the cylinder of the stove into the room.

k, k the dotted red lines below the stove, show the opening in the hearth for the cold air and the red arrows indicate its direction. The heavy dotted black line near the back connecting the two upright side flanges g, g, over which the external air passes in, shows the lower horizontal flange, forming with the side flanges the channel for the air from the outside on its way into the apartment. The dotted blue lines (circular) above the back part of the stove show the position of the pipe for the final exit of the smoke into the chimney.

i, is the rod connected with the damper in the smoke pipe.

©2016 Patricia Bixler Reber
Forgotten history of Ellicott City & Howard County MD