CHAPTER IV.

BATTERIES, OBSERVATORIES, AND MAGAZINES.

42. Batteries Defined, etc., 42

43. General Requirements of Siege-batteries, 42

44. Construction of Batteries for Field-guns, 43

45. Batteries for Siege-guns and Howitzers, Elevated and Sunken,--General Considerations, 44

46. Screens, 45

47. Exposed Sunken Battery, 46

48. Tracing the Battery, 47

49. Constructing the Central Passage and Splinter-proof, 48

50. Constructing the Battery, 49

51. Alternative Construction, 50

52. Splinter-proofs (additional), 50

53. Sunken Battery in a Parallel, 51

54. Battery behind Crest of a Hill, 53

55. Batteries on Sloping Ground, 53

56. Embrasures, 53

57. Observatories, 54

58. Drainage, 55

59. Mortar-batteries, 55

60. Magazines, 57

61. Cover for Magazines, 58

62. Location of Magazines, 58

63. Construction of a Magazine subject to Direct Fire only, 60

64. Manner of Executing the Work, 61

65. Mined Magazines, 61

66. Elevated Magazines, 62

67. Precautions against Dampness, 63