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32 Every preparation for adjusting the com- passes was made before leaving Chi- cago (these details are mentioned here merely to show what an easy matter it is to make a mistake, while doing every-- thing in your power to guard against it). It was late in the afternoon when we got outside and swung the vessel for ad- justment, and as there was not. sufficient time before the sun would dip below the horizon, only the steering compass was adjusted; and this for lack of time was only adjusted for semi-circular deviation. About 20 minutes before sun set the ves- sel was put on the usual course for Point Betsey, by means of the pelorus and sun's azimuths (the c. m.c. N by E%4E): and when steadied the steering compass showed N by E. During the next Io minutes three different azimuths were taken, and the last one showed that the compass was affected by % point Wly. Dev., and instead of showing the ship's head c. m. N by EME, it showed it to be N by E%E (the man at the wheel was keeping her steady on N by E all the 'time as he had been told). The course was altered to N by E%E (ported an eighth) to counteract this. Right here then showed what we have mentioned, namely, that the ship's magnetism, in some cases, is slow in changing and ac- quiring new relations with the earth's in- ductive forces, when the vessel's head is considerably changed in azimuth, as was the case here. It was fully 10 minutes that the vessel was steadied on this course before this error was discovered, which showed that the vessel's iron had not passed through the various phases of magnetism and settled down to a perma- nent state as soon as it should have un- der ordinary conditions. This goes to show that in determining the deviation of the compass that when a vessel is steadied on the course even so long as five minutes, that the time is insufficient in some cases. This is a point which wants to be remembered by the student as well as the navigator, and is something that but very little atten- tion is paid. To go on with our story: THE COURSE WAS VERIFIED BY THE NORTH STAR, That night the course was verified by the north star by the pelorus and found to be correct. We were due at Point Betsey along about noon the next day. As .it was hazy Little Point 'Sable was not seen on the course, at least it was not reported, and if it had been it was too early in the mid watch to have turned out to get its bearing. The loom of the land at Big Point Sable was seen, but no bearing could be taken on account of the haze. It looked farther off than it ought to, but there was no proof of this, inasmuch as we were more than certain that the vessel was making the right course (she was making the course all TRE Marine REVIEW right according to figures, but it was not the one we were figuring on). We passed several boats that were inside of us some five or six miles, that were sup- posed to be steering the Chicago course (and they were, too), but as we were steering by our own compass and not by the other fellow's, we did not let this bother us, though it set us to thinking; another thing, we were on the deep wa- ter side of our point of destination (ac- cording to the other fellows), so that stranding, or a chance of stranding, was out of the question. As the sun's bear- ings, for which the course was set were taken under the most favorable circum- stances (when the sun had a low alti- tude) we could see no good reason why we were not on the right track, notw:th- standing all these unfavorable signs. But when Point Betsey was made we were some 11 miles off when abeam, instead of four miles, or seven miles wrong. Here was a puzzler. We were almost positive that the course was set right at the start. A mistake could very easily have been made in the watch time for the azimuths, but as this had been verified a few hours before leaving -Chicago. this was out of the question. Current was suggested as being the cause, but as there were no indications of current, as judged from the weather we had had for the past 24 hours, and from present con- ditions, this was dispelled. However, we went diligently to work in an endeavor to locate the real trouble. The azimuth work was examined and found correct. The steering compass was looked over, and the wheelsmen questioned in regard to several matters; the pilothouse was next looked over to see if anything had under- gone a change from the day before, and here everything was apparently all right. It must have been in the steering, but whatever it was we were. afraid that it would never be brought to light. We next verified the amidship fore-and-aft line of the vessel to see if the steering compass was parallel therewith. This was found correct enough. We next ex- amined the pelorus stand to see if this was correctly placed, and here we were rewarded for our pains, for it was found to be considerably slewed from a line parallel with the fore-and-aft line of the ship; and as afterwards proved was the whole cause for the wrong' steering. As the sun was still very, high (a lit- tle after noon) and not favorable for azimuths, nothing was done until in the vicinity of South Manitou Island. Dur- ing the meantime a set of azimuths was tabulated for a certain position (off the light) and at the proper time the vessel was swung to resume the work of ad- justing the compasses. The pelorus stand was not touched, but remained in its place, though correct lines were drawn so that when the time came for chang- ing it it would only take a few minutes to do so. When the time came for tak- ing the azimuths the first thing done was to put the ship's head, correct magnetic N by EME by the pelorus and the course by steering compass compared. After be-_ ing thoroughly steadied on the course the compass showed the same course that we had steered from Chicago to Point Bet- sey, namely, N by E%E. This was suf- ficient proof that the pelorus was the cause of the trouble and in order to be doubly sure, the pelorus stand was moved to its correct position, and the-ship's head steadied again c. m. N by E™%E by pe- lorus. When sufficiently steadied on this course the steering compass read N by EME, little easterly (good 2 degrees dif- ference). As we were about seven miles 'farther off Point Betsey than we should have been, an error of 2 degrees on this run of 200 miles would just about make this, which again was convincing proof. This then goes to show what a little carelessness on our part in not verify- ing the position of the pelorus stand af- ter it was fastened to the deck. Here no trouble came of it, but there are many times when this much of an error would lead to serious trouble. We were almost - positive that the vessel was on the right course from the fact that everything done was performed under-such favorable cir- cumstances. There was nothing wrong with the course according to the fig- ures; and she was making the course ac- cording to these figures, but not the one that we were figuring and counting on. This same experience taught us an ex- cellent lesson, and that is, that it is not liable to occur again. After the com- passes were adjusted and the boat swung for a table of residual, or remaining cor- rections, no trouble was experienced in making good the courses shaped accord- ing to these corrections. The alidade is a modification of the pelorus, but is fitted on top of the bin- nacle, and can be removed at pleasure. It is used as an azimuth for the cor- rection of the compass, and is especially adapted for taking bearings of land ob- jects. It is simple and strong and is made to fit any binnacle top. The instrument is made entirely of brass, and is, therefore, non-magnetic. The dial plate and the cross bar carrying the sight vanes work independently of each other, and either of them can be set to any reading at pleasure. The feet, or down rights, from this cross bar acts as an indicator for reading the bearing on the dial. Their centers are marked so that by following the line down with the eye, it will show where it cuts a division on the dial and the bearing is thus read off. This instrument is nothing compared with: the pelorus.