" S. P.," Brooklyn, New York, remarks: "In reading your last issue, I found several communications in regard to heaters for greenhouses. I have also heard several gardeners talking in reference to steam as a means of heating, in place of our old friend, the 'hot water apparatus.'

"I think it would be well for all interested in the matter, to study the question in all its bearings before making so decided and radical a change.

"In the first place, up to the present time, I have found no means of heating greenhouses to give such universal satisfaction as the hot water apparatus has done, and when put up in a proper manner by good mechanics, have always found it reliable. It is economical in the use of fuel, requires very little attention, and any man of ordinary intelligence can manage it. When a greenhouse is properly piped, and has a boiler of sufficient capacity to heat the same without forcing (which should always be the case), we can fix our fires at 10 p. m., and find everything going along nicely at six o'clock the next morning, and this can be done in the coldest weather, if the conditions in regard to pipe and boiler be complied with. The hot water apparatus, if put in properly, costs very little for repairs, as there is nothing to get out of order except the boiler, and that is good for ten or twelve years. I have known cases where they have been in use for twenty years, without any repairs save a few new grates. In a hot water apparatus a very slow fire will keep the water circulating all night, and by so doing gives us the proper amount of heat from very little fuel.

Now the question arises, will a steam heater do all this? For myself, I am afraid not.

"I think that a steam apparatus will burn more fuel, for it is actually necessary that steam be kept up, or the heat goes down at once, and to keep up this steam we must have a lively fire. To get that permanence of temperature so much desired in greenhouses, a steam heater would demand almost constant attention.

" The parties getting up these heaters claim that they have self-regulating dampers, etc, that will just keep the steam and fire to a certain pitch ; but my experience with all such contrivances is, that it takes very little to put them out of order, and then they are worse than useless. In all steam boilers there is more or less trouble with sediment, and these for greenhouses would be no exception to this general rule, and would require to be cleaned out occasionally or great injury would result to the boiler. No matter how safe you try to make a steam boiler, if placed in the hands of inexperienced parties, there is more or less danger of explosion.

" I could say much more on this subject, but not wishing to trespass too much on your valuable space, I will conclude by stating that, in my opinion, before steam can take the place of our old friend and banish him from the greenhouse, its advocates must make it as safe, convenient, economical, permanent of temperature, and easy of management as the hot water apparatus".

[It is not likely that steam will take the place of hot water for small greenhouses ; it is only for the larger establishments that it seems a great advance. There are some objections, as there are to all these projects, but the balance of advantages as against the objections, decides.

As to consumption of coal, we know of one large building heated by steam, which once had furnaces in the cellar. The average of coal used the past two winters, was no more than of the two winters previous. Fires are left on Saturday night, and the building has very little decrease in temperature on Monday morning. - Ed. G. M].