Quarter  Alargar (Distance from course) Avanzar (Advance on true course)  Ritorno (Return to course) Avanzo di ritorno (Advance during return) 1 20 98  51 50 2 38 92  26 24 3 55 83  18 15 4 71 71  14 10 5 83 55  12 6 6 92 38  11 4 7 98 20  10 2 8 100 0  10 0 For every 100 miles For every 10 miles alargar 400px|Calculating the ritorno and avanzo di ritornoThis is what the third column of the toleta is for. The return angles are expressed as quarters from the intended course bearing (not the current course bearing). In our example, the mariner intended to go east, but has been sailing southeast-by-east for 100 miles. Given the winds, he decides it is best to return to the original course by re-orienting the ship east-northeast (ENE, "Greco-Levante"). ENE is two quarter-winds above the intended bearing, East, so now he looks at second row ("quarters = 2") on the table. In the third column , the ritorno,  shows the number 26. This represents the required number of miles he must travel on ENE bearing for every 10 miles of alargar . Remember, his alargar (distance from intended course) was 55 miles. So in order to return to his intended course he must travel 5.5 × 26 = 143 miles on ENE. In other words, he needs to hold his ENE bearing for 143 miles; once that distance is travelled , he should straighten his ship East , and he will be exactly  on the intended course. The  final column (avanzo di ritorno) gives the length on the intended course he has made good by his return travel. This is also expressed in terms per 10 miles alargar. His alargar was 55, and his angle of return was ENE (thus q = 2), that means his avanzo di ritorno is 5.5 × 24 = 132. In other words, if everything goes right, and our mariner holds his ENE bearing for 143 miles (ritorno), then during that return, he will have covered an additional 132 miles on his intended eastward course (avanzo di ritorno). Finally, the total avanzo on the eastward bearing is the avanzar during the deviation (83 miles) plus the avanzo di ritorno (132 miles) , thus on the whole, he has covered 83 + 132 = 215 miles on the intended course. Measuring that distance on the map from the starting point (A), the mariner can figure out his exact current position.
Quarter (Angle of deviation) Alargar (Distance from course) Avanzar (Advance on true course) Quarter (Angle of return) Ritorno (Return to course) Avanzo di ritorno (Advance during return) 1 20 98 1 51 50 2 38 92 2 26 24 3 55 83 3 18 15 4 71 71 4 14 10 5 83 55 5 12 6 6 92 38 6 11 4 7 98 20 7 10 2 8 100 0 8 10 0 For every 100 miles For every 10 miles alargar 400px|Calculating the ritorno and avanzo di ritornoCalculating the return course is what the last three columns of the toleta are for. In the fourth column, the return angles are expressed as quarters from the intended course bearing (not the current course bearing). In our example, the mariner intended to go east, but has been sailing southeast-by-east for 100 miles. Given the winds, he decides it is best to return to the original course by re-orienting the ship east-northeast (ENE, "Greco-Levante"). ENE is two quarter-winds above the intended bearing, East, so now he looks at second row ("quarters = 2") on the fourth column of the table. The fifth column is the ritorno, the distance he must travel on the chosen return angle to recover the original course. Given he has chosen to return by ENE bearing (q = 2), then he must read the second row of the ritorno column, which shows the number 26. This represents the required number of miles he must travel on ENE bearing for every 10 miles he deviated . Remember, his alargar (distance from intended course) was 55 miles. So in order to return to his intended course he must travel 5.5 × 26 = 143 miles on ENE. In other words, he needs to hold his ENE bearing for 143 miles; once that distance is traveled , he should straighten his ship east , and he will be exactly back on the intended course. The sixth and final column (avanzo di ritorno) gives the length on the intended course he has made good by his return travel. This is also expressed in terms per 10 miles alargar. His alargar was 55, and his angle of return was ENE (thus q = 2), that means his avanzo di ritorno is 5.5 × 24 = 132. In other words, if everything goes right, and our mariner holds his ENE bearing for 143 miles (ritorno), then during that return, he will have covered an additional 132 miles on his intended eastward course (avanzo di ritorno). Finally, to calculate the total distance made good (total avanzo) on the eastward bearing by his whole adventure, he must add the avanzar during the deviation (83 miles) plus the avanzo di ritorno (132 miles) . Thus on the whole, he has covered 83 + 132 = 215 miles on the intended course. Measuring that distance on the map from the starting point (A), the mariner can figure out his exact current position.
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