Writing in one of the magazines lately, Mr Anthony Trollope says the most difficult thing that a man has to do is to think. There are many, he tells us, who can never bring themselves really to think at all, but do whatever thinking is done by them in a chance fashion, with no effort, using the faculty which the Lord has given, because they, as it were, cannot help themselves. To think is essential, all will agree, continues this pleasant writer, and that it is difficult most will acknowledge who have tried it. This passage might be studied with advantage by some writers of the horticultural press. No one will deny, we think, that the contributions sent to the gardening papers by the practical section of the fraternity are, for the most part, sound and practical, as well as conscientiously written; but neither can it be denied that some horticultural writers belong to that class which Anthony Trollope says never bring themselves to think at all, or else think in a chance fashion only. When such writers confine themselves to a relation of their practice and its results, they do not err so seriously; it is when they begin to speculate on the causes of things that their lamentable incapacity and unreasoning dogmatism appear.

There is no harm in a writer stating his opinions, of course, and he may be excused for being positive in these when he is certain of what he writes; but censure, and, it may be added, pity, only can be extended to a man who, on the strength of his own insufferable conceit and ignorance, attempts to ride rough-shod over his neighbours in matters of practice and opinion. We sometimes laugh at the foibles and conceits of scientific men and savants, but, judged by their public speeches and writings, it must be confessed that they are, as a rule, both logical and honest in all that they do, - and that much cannot be said for some writers on horticultural topics. Such men as Darwin, Owen, Huxley, and others, and, we are glad to say, plenty of good horticulturists, exhibit a praiseworthy consistency and honesty in their writings and investigations that might well be imitated by horticultural and arboricultural scribes of doubtful calibre and reputation, whose vanity leads them to commit errors and absurdities that would make them hide their heads in confusion, could they only "see themselves as others see them." Some writers presume upon their age and experience on some particular line, that has rendered them oblivious to everything else, to scold everybody who differs from them, no matter on what; while others are quite as presumptuous and dogmatic upon even less experience and very slender abilities, either as teachers or practitioners.

The miserable sophistry and worse logic displayed in numerous instances is truly pitiable. Very accurate reasoning and clearness of expression is not to be expected from men who have not been trained to think logically and methodically; but it would be more to the credit of those to whom these remarks apply if they would but concentrate their attention in an attempt to tell in an intelligible manner what they do know, and are sure about, instead of dealing in vague generalities and platitudes which serve no purpose and only bring the writer into contempt.

I am pleased to see, Mr Editor, that you have at last got out of hot water. You should really make allowance for the capacities of your readers, and not tax them too severely. In attempting to gather up the threads of the discourse in a sequent manner, our mind was fast approaching a chaotic condition, and we have, perforce, been compelled to discontinue the study. Before we begin again we mean to follow the example of Descartes, and get all former ideas and impressions effaced from our mind, and begin with a clean state. How we have commiserated the Editor over the ' copy" ! There was a rumour abroad that he had to fly to the solitudes of the Lake district about the most acute period of the discussion, in order to restore his mental equilibrium. If we have been wrongly informed, Mr Editor, we beg your pardon. Now let us see how far on we have got now. For the last twenty years or more these periodical hot-water storms have occurred with the utmost regularity, and scourged every horticultural paper in the land, until the subject now frightens editors about as much as the "Peronospora infesteus," and the "Resting Spore," pace W. G. S. Some twenty years ago, or rather more - for we speak from memory - Mr Thomson of Dalkeith wrote, in the ' Scottish Gardener,' that he could heat something like 500 or 600 feet of 4-inch piping in about an hour and forty minutes, by a moderate-sized retort boiler.

In other words, from the time the fire was lit till the heat could be felt in the return-pipe close to the bolier, 100 minutes elapsed. The pipes were arranged on various levels in the usual way, and heated numerous divisions. Ye senior and junior hot-water wranglers, have ye accomplished more than this? What is the practical outcome of your hair-splitting disquisitions on hot-water circulation? - a question that has been settled long ago by eminent engineers and others, who at least understand the matter. Discussions on this subject, as in the present instance, have generally been based on the question of sunken stoke-holes, which, it seems taken for granted, must be avoided if possible. But are sunken stoke-holes such an unmixed evil? "We know gardens where all the stoke-holes have been kept under ground by special desire. Nor did they cost more than above-ground structures would have done; and what would have been an obnoxious eyesore was abolished.

While on this subject it may be mentioned that means have been discovered whereby petroleum can be burnt effectively under boilers at a cost about equal to coal, but in a way that presents important advantages over the latter. More will likely be heard of the discovery by-and-by, if it accomplishes all that is claimed for it; but as yet we believe it has only been tried under steam-boilers.