This section is from the book "Hunting: A Manual of Fox, Hare, Stag & Otter Hunting", by J. Otho Paget. Also available from Amazon: Hunting: A Manual of Fox, Hare, Stag & Otter Hunting.
Halloas are at all times to be regarded with extreme care, as they will very often be the means of putting you on the line of a fresh fox ; but you must take advantage of them occasionally, and when you have any doubt, you had better send a whip on to make inquiries.
I have endeavoured to prove that the hound possesses the power of distinguishing one scent from the other, and our task is to instil into him that by noting this distinction and adhering to one line, he is most likely to catch his fox. His instinct teaches him to run a scent, but his education and power of reasoning must teach him the best way of attaining the desired end. If you object to animals being credited with a reasoning power, then give it another name, but my stock of language does not supply me with any other word. The boundary-line between instinct and reason is difficult to define. However tender-nosed a hound may be, he will very seldom develop a capacity for hunting a road until he is in his third or fourth season. A good road hound is not of so much importance in the pursuit of the fox as in that of the hare, but he is very useful sometimes. You will see the whole pack at fault on a road and one hound will go gaily on throwing his tongue, whilst the others can make nothing of it; but yet this hound will not be noted for any greater excellence in the fields. Why is this ? I have no answer to this question; but I imagine there is much less scent on a road, and also that the different surface entirely changes its character. The majority of the pack are confused by this change ; but the one hound, having more reasoning power than his fellows, has noticed the change on previous occasions, and makes allowance when it occurs again. Hounds differ in their individual characters quite as much as human beings, and though one that is a fool may have an excellent nose, he will never shine above the others in his work. One of the greatest objections against breeding hounds too close is that their brain-power becomes reduced.
I have still a few more words to say on the subject of scent, from which we seem to have drifted into a discussion on other things. The two elements which have the greatest effect on scent are atmosphere and soil, but in what way they act for good or evil no one yet has been able to determine. We know that a light, sandy, or very porous soil is bad for scent, but we do not know why. My idea is that these soils are, unless flooded with wet, always absorbing moisture from the air, and that they draw down scent at the same time. A clay soil absorbs moisture very slowly, except arable land that has no crop and in exceptionally dry weather. I should say that the most favourable time for hounds to run is when the atmosphere is in such a state that it is nearly of the same weight as scent, with just a slight leaning to the light side. When the fox or other animal starts off, his scent is left in a little cloud behind him, which, when it and the air are nearly of the same weight, sinks very gradually to the ground. Then, if it falls on grazing ground, it will cling for some time to the herbage, whilst that falling on a dry, barren surface will quickly disappear. Of course, when the air is the heaviest, your scent will disappear skywards, and your only chance of a run is to keep near your fox. On those days, which occur once in two or three seasons, when hounds can race over every kind of country and every variety of soil, I believe that air and scent have just happened to be evenly balanced. It is quite easy to understand that the chance cannot occur often, as with two such light materials, the slightest difference must turn the scales either way.
Sheep, cattle, and horses all destroy scent, or rather, I should say, they confuse the hounds by mixing up their own strong smell with that of the fox. I think it does hounds good to occasionally let them hunt out a cold line, but not when there are other scents combined with that of the fox. Manure, artificial and otherwise, is strong enough for us to smell, and it therefore must get in the hound's nostrils and overpower the faint scent of an animal. When you see that any of the above causes have brought the pack to a check, do not wait for them to cast themselves or puzzle it out, but lift them forward at once beyond the affected area. When, however, you can see nothing that you think likely to have affected the scent, it is better to leave hounds alone, as with a very weak scent they will not be inclined to stoop again after you have once got their heads up.
At the time when a frost is going off scent is generally supposed to be bad, and later in the same day, when the frost is all gone, you will notice a marked improvement. Fox-hunting is not carried on in a hard frost, but in my experience with beagles hunting a hare, I have known some extraordinarily good scents when the ground has been as hard as iron.
I have set down a few facts concerning scent, and have advanced a few theories, but I shall leave it to you to draw your own conclusions. Never be disheartened because a day looks unpro-pitious according to all the rules you have ever heard, and if there is no scent in the morning, hope for better luck in the afternoon. Every one who has ever hunted has some pet idea about scent, which, however, he is certain to see confounded before the end of his experience. Tom Firr disliked seeing a blue mist, and, I think, many other huntsmen consider it an ill omen, but they must have occasionally seen hounds run fast with it on the horizon. My ideal day would be without a blue mist, or a haze of any kind ; a grey sky looking down on a clear landscape, with the fences outlined black and sharp against the green of the fields ; then a gentle breeze should be blowing, cool and damp, from any other point of the compass except the west. Such is the day I would choose for hunting, and very probably it would turn out to be the worst scenting-day of the season.