ENGINEMAN  1  &  C commanding  officer  (or  engineer  officer)  enters such remarks over his signature as he deems ap- propriate. After the log has been signed by the commanding  officer,  no  change  is  permitted without his permission or direction. Completed Engineering Log sheets are filed in  a  post-type  binder.  Pages  of  the  log  are numbered consecutively with a new series of page numbers  commencing  with  the  first  day  of  each calendar  year. ENGINEER’S  BELL  BOOK.—The Engineer’s Bell Book, NAVSEA 3120/ 1 (figure 2-2), is a record of all bells, signals, and other orders  received  by  the  throttleman  regarding movement of the ship’s propellers. Entries are made in the Bell Book by the throttleman (or an assistant) as soon as an order is received. Entries may be made by an assistant when the ship is entering  or  leaving  port,  or  engaging  in  any maneuver which is likely to involve numerous or rapid speed changes. This procedure allows the throttleman  to  devote  his  undivided  attention  to answering  the  signals. The Bell Book is maintained in the following manner: 1. A separate bell sheet is used for each shaft each day, except where more than one shaft is controlled  by  the  same  throttle  station,  in  which case the same bell sheet is used to record the orders for all shafts controlled by the station. All sheets for the same date are filed together as a single record. 2. The time of receipt of the order is recorded in column number 1 (figure 2-2). 3. The order received is recorded in column number 2. Minor speed changes (generally re- ceived  via  revolution  telegraph)  are  recorded  by entering the number of rpm ordered. Major speed changes  (normally  received  via  engine  order telegraph)  are  recorded  using  the  following symbols: 1 / 3     — ahead 1/3 speed 2/3 —  ahead 2/3 speed I —   ahead standard speed II —  ahead  full  speed III —  ahead flank speed Z — stop B1/3 —back 1/3 speed 2-4 B2/3 — back 2/3 speed BF — back full speed BEM    —back emergency speed 4.  The  number  of  revolutions  corresponding to the major speed change ordered is entered in column 3. (NOTE: When the order received is recorded  as  rpm  in  column  2  (minor  speed changes), no entry is made in column 3.) 5. The shaft revolution counter reading (total rpm) at the time of the speed change is recorded in  column  4.  The  shaft  revolution  counter reading—as  taken  hourly  on  the  hour,  while underway—also is entered in column 4. Ships  and  craft  equipped  with  controllable reversible pitch propellers record in column 4 the propeller pitch in feed and fractions of feet set in response to a signaled speed change, rather than the shaft revolution counter readings. The entries for astern pitch are preceded by the letter B. Each hour on the hour, entries are made of counter readings, thus facilitating the calculation of engine miles  steamed  during  those  hours  when  the propeller pitch remains constant at the last value set in response to a signaled order. Before going off watch, the EOOW signs the Bell Book on the line following the last entry for his  watch  and  the  next  EOOW  continues  the record  immediately  thereafter.  In  machinery spaces where an EOOW is not stationed, the bell sheet is signed by the watch supervisor. The Bell Book is maintained by bridge per- sonnel  in  ships  and  craft  equipped  with  con- trollable reversible pitch propellers, and in which the engines are directly controlled from the bridge. When  control  is  shifted  to  the  engineroom, however,  the  Bell  Book  is  maintained  by  the engineroom personnel. The last entry made in the Bell Book on the bridge indicates the time that control is shifted; and the first entry made in the Bell Book in the engineroom indicates the time that  control  is  taken  by  the  engineroom. Similarly, the last entry made by engineroom per- sonnel indicates when control is shifted to the bridge. When the Bell Book is maintained by the bridge personnel, it is signed by the officer of the deck (OOD) in the same manner as prescribed for the EOOW. Alterations or erasures are not permitted in the Bell Book. An incorrect entry is corrected by