For twenty minutes or more he continued his researches, measuring with the most exact care the distance between marks which were entirely invisible to me, and occasionally applying his tape to the walls in an equally incomprehensible manner.
In one place he gathered up very carefully a little pile of grey dust from the floor, and packed it away in an envelope. Finally, he examined with his glass the word upon the wall, going over every letter of it with the most minuteexactness. This done, he appeared to be satisfied, for he replaced his tape and his glass in his pocket.
福爾摩斯前後共檢查了二十分鐘，他小心翼翼地測量了一些痕跡之間的距離。這些痕跡，我是一點也看不出來的。他偶爾也令人費解地用捲尺測量牆壁。
後來，他非常小心地從地板上的一個地方捏起一小撮灰色塵土，並且把它放進一個信封裡。接著，他用放大鏡檢查了牆壁上的血字，並非常仔細地觀察了每一個字母。最後，他似乎很滿意了，終於把捲尺和放大鏡裝進了衣袋中。
注意：minute在這裡是作為形容詞使用的，表示極小的，細微的，詳細的。在翻譯時需要注意。
例如：
Our lawyer went over the contract in minute detail.
（我們的律師仔細地閱讀了那份合同。）
I remembered in minute detail everything that had happened.
（我對發生的每件事的細枝末節都記得清清楚楚。）
今天的知識點，你記住了嗎