"'Why should we give it?'
"'For the sake of the trust.'
"'The original has no date, but is in the spelling of the middle of theseventeenth century,' remarked Musgrave. 'I am afraid, however, that itcan be of little help to you in solving this mystery.'
"'At least,' said I, 'it gives us another mystery, and one which is evenmore interesting than the first. It may be that the solution of the onemay prove to be the solution of the other. You will excuse me, Musgrave,if I say that your butler appears to me to have been a very clever man,and to have had a clearer insight than ten generations of his masters.'
"'I hardly follow you,' said Musgrave. 'The paper seems to me to be ofno practical importance.'
"'But to me it seems immensely practical, and I fancy that Brunton tookthe same view. He had probably seen it before that night on which youcaught him.'
"'It is very possible. We took no pains to hide it.'
"'He simply wished, I should imagine, to refresh his memory upon thatlast occasion. He had, as I understand, some sort of map or chart whichhe was comparing with the manuscript, and which he thrust into hispocket when you appeared.'
"'That is true. But what could he have to do with this old family customof ours, and what does this rigmarole mean?'
"'I don't think that we should have much difficulty in determiningthat,' said I; 'with your permission we will take the first train downto Sussex, and go a little more deeply into the matter upon the spot.'
"The same afternoon saw us both at Hurlstone. Possibly you have seenpictures and read descriptions of the famous old building, so I willconfine my account of it to saying that it is built in the shape ofan L, the long arm being the more modern portion, and the shorter theancient nucleus, from which the other had developed. Over the low,heavily-lintelled door, in the centre of this old part, is chiseled thedate, 1607, but experts are agreed that the beams and stone-work arereally much older than this. The enormously thick walls and tiny windowsof this part had in the last century driven the family into building thenew wing, and the old one was used now as a store-house and a cellar,when it was used at all. A splendid park with fine old timber surroundsthe house, and the lake, to which my client had referred, lay close tothe avenue, about two hundred yards from the building.
"I was already firmly convinced, Watson, that there were not threeseparate mysteries here, but one only, and that if I could read theMusgrave Ritual aright I should hold in my hand the clue which wouldlead me to the truth concerning both the butler Brunton and the maidHowells. To that then I turned all my energies. Why should this servantbe so anxious to master this old formula? Evidently because he sawsomething in it which had escaped all those generations of countrysquires, and from which he expected some personal advantage. What was itthen, and how had it affected his fate?
"It was perfectly obvious to me, on reading the ritual, that themeasurements must refer to some spot to which the rest of the documentalluded, and that if we could find that spot, we should be in a fair waytowards finding what the secret was which the old Musgraves had thoughtit necessary to embalm in so curious a fashion. There were two guidesgiven us to start with, an oak and an elm. As to the oak there could beno question at all. Right in front of the house, upon the left-handside of the drive, there stood a patriarch among oaks, one of the mostmagnificent trees that I have ever seen.
"'That was there when your ritual was drawn up,' said I, as we drovepast it.
"'It was there at the Norman Conquest in al
l probability,' he answered.'It has a girth of twenty-three feet.'
"'Have you any old elms?' I asked.
"'There used to be a very old one over yonder but it was struck bylightning ten years ago, and we cut down the stump.'
"'You can see where it used to be?'
"'Oh, yes.'
"'There are no other elms?'
"'No old ones, but plenty of beeches.'
"'I should like to see where it grew.'
"We had driven up in a dog-cart, and my client led me away at once,without our entering the house, to the scar on the lawn where theelm had stood. It was nearly midway between the oak and the house. Myinvestigation seemed to be progressing.
"'I suppose it is impossible to find out how high the elm was?' I asked.
"'I can give you it at once. It was sixty-four feet.'
"'How do you come to know it?' I asked, in surprise.
"'When my old tutor used to give me an exercise in trigonometry, italways took the shape of measuring heights. When I was a lad I workedout every tree and building in the estate.'
"This was an unexpected piece of luck. My data were coming more quicklythan I could have reasonably hoped.
"'Tell me,' I asked, 'did your butler ever ask you such a question?'