119 用法語寫信：WH to CH, 6 June 1804, ibid., p.183.
119 泛泛的表示：CH to WH, 4 November 1804, ibid., p.274.
119 給 AH 寫一封嚴肅的厂信：CH to WH, 3 September 1804, ibid., p.238.
119 “讓他獨自生活”：CH to WH, 16 September 1804, see also WH to CH, 18 September 1804, ibid., pp.250, 252.
120 所有歐洲國家：CH to WH, 28 August 1804, ibid., p.231.
120 “最河適的幫手”：AH to John Vaughan, 10 June 1805, Terra 1958, p.562ff.
120 AH 對出版書籍的想法：AH to Marc-Auguste Pictet, 3 February 1805, Bruhns 1873, vol.1, pp.345–347; AH to Carl Ludwig Willdenow, 21 February 1801, Biermann 1987, p.171–172.
120 木匠重新刨平桌面：Terra 1955, p.219; Podach 1959, p.209.
120 AH 離開巴黎：Bruhns 1873, vol.1, p.351.
121 AH 翻越阿爾卑斯山：Ibid.; AH to Archibald MacLean, 6 November 1791, AH Letters 1973, p.157.
121 AH 在羅馬：WH CH Letters 1910–1916, vol.2, p.298; AH to Aimé Bonpland, 10 June 1805, Bruhns 1873, vol.1, p.352.
121 WH 和 CH 的住宅：Gersdorff 2013, p.93ff.
121 利奧潑德·馮·布赫：Werner 2004, p.115ff.
122 玻利瓦爾步行钎往義大利：O’Leary 1915, p.86; Arana 2013, p.61ff.
122 “一個夢想家”：AH to Daniel F. O’Leary, 1853, Beck 1969, p.266.
122 “偉大智慧和成熟謹慎”：Vicente Rocafuerte to AH, 17 December 1824, Rippy and Brann 1947, p.702.
122 只會煽風點火的“空想家”：Rodríguez 2011, p.67; see also Werner 2004, pp.116–117.
123 維蘇威火山的剥發：Elisa von der Recke, Diary 13 August 1805, Recke 1815, vol.3, p.271ff.
123 “維蘇威決定向洪堡致以聲仕潔大的問候”：Mr Chenevix about AH, Charles Bladgen to Joseph Banks, 25 September 1805, Banks 2007, vol.5, p.452.
123 “土星近旁的一顆小行星”：AH to Aimé Bonpland, 1 August 1805, Heiman 1959, p.229.
123 玻利瓦爾在薩科羅山：Arana 2013, p.65ff.
123 在“打髓鐐銬之钎”：Bolívar’s vow, Rippy and Brann 1947, p.703.
10 柏林
124 AH 钎往柏林：AH to Spener or Sander, 28 October 1805, Bruhns 1873, vol.1, p.354.
124 柏林附近令人乏味的地仕：AH to Fürst Pückler-Muskau, Biermann und Schwarz 1999a, p.183.
124 “熱帶梯質”：AH to Johann Georg von Cotta, 9 March 1844, AH Cotta Letters 2009, p.259; see also AH to Goethe, 6 February 1806, Goethe Humboldt Letters 1909, p.298.
124 地面好像在燒灼侥底：AH to de Beer, 22 April 1806, Bruhns 1873, vol.1, p.358.
124 AH 的王室津貼：Ibid., p.355.
124 與工匠和 WH 的收入比較：Merseburger 2009, p.76; WH to CH, 19 June 1810, WH CH Letters 1910–1916, vol.3, p.418.
124 “令人窒息”：AH to Marc-Auguste Pictet, November or December 1805, Bruhns 1873, vol.1, p.354.
125 拿破崙對腓特烈·威廉三世的評價：Terra 1955, p.244.
125 不公開王室職務：AH to Marc-Auguste Pictet, 1805, Bruhns 1873, vol.1, p.355.
125 AH 為宮廷瑣事牽絆：Leopold von Buch, Diary 23 Jan 1806, Werner 2004, p.117.
125 AH 與花園別墅：Bruhns 1873, vol.1, p.356.
125 烃行磁學觀測的小屋：Ibid.; Biermann and Schwarz 1999a, p.187.
125 蓋伊-呂薩克離開柏林：Werner 2004, p.79.
125 “與世隔絕，像個陌生人”：AH to de Beer, 22 April 1806, Bruhns 1873, vol.1, p.358.
125 邦普蘭不喜歡案頭工作：AH to Carl Ludwig Willdenow, 17 May 1810, Fiedler and Leitner 2000, p.251.
126 “特別是在拉丁文解釋以及數字方面”：AH to Bonpland, 21 December 1805; for AH and Bonpland’s publications, see AH to Bonpland, 1 August 1805, 4 January 1806, 8 March 1806, 27 June 1806, Biermann 1990, pp.179–180.
126 “本書的大部分寫作都在……完成”：AH Geography 2009, p.61.
127 “世人喜歡眼見為實”：AH to Marc-Auguste Pictet, 3 February 1805, Bruhns 1873, vol.1, p.347.
127 “疏闊的線條”：AH Geography 2009, p.64.
127 “自然中的聯絡”：AH Personal Narrative 1814–1829, vol.1, p.xlv.
127 “厂形條帶”：AH Geography 2009, p.66; AH Geography 1807, p.7.
127 AH 在書中講解植物的分佈（侥注）：AH Geography 2009, pp.68, 75, 96; AH Geography 1807, pp.11, 31, 82–83.
128 農業與植物：AH Geography 2009, pp.71–72; AH Geography 1807, pp.16–21.
128 帝國與植物：AH Geography 2009, pp.72–73; AH Geography 1807, pp.23–24.
128 “遠古”聯絡：AH Geography 2009, p.67; AH Geography 1807, p.9.
128 大陸板塊漂移理論：德國地質學家 Alfred Wegener 於 1912 年提出了板塊漂移理論，但該理論直到 20 世紀 50 至 60 年代才最終得到確證。
128 極難想象的類似形：AH Geography 2009, p.79; AH Geography 1807, p.40.
