25 Ground 5 alleges that the judge erred in fact and in law in not finding that the respondent 'could have determined' that the ground level of the lots was not the base datum level for the restrictive covenant and accordingly 'acquiesced' in the appellants' breaches. In substance, it alleges that the respondent acquiesced in the appellants' breach of covenant by her omission to ascertain the true datum level in order to establish whether the appellants' structures were in breach of covenant. It does not lie in the mouth of the appellants to assert that the respondent should have established that the appellants were in breach of covenant before the respondent purchased her lot when the appellants had themselves not taken the trouble to establish the true datum level and had compounded that omission by deliberately building structures to a height which, even on their own erroneous assumption of the true datum level, they knew to be in breach of the restrictive covenant. Further, by this ground, the appellants do not allege laches, but rather acquiescence in what may be regarded as the proper meaning of the term, namely, acquiescence in the sense of abstaining from interference while the violation of one's rights is in progress: Ramsden v Dyson [1866] LR 1 HL 129; Duke of Leeds v Earl of Amherst (1846) 2 PH 117, 122; Meagher RP, Heydon JD & Leeming MJ_, Meagher, Gummow and Lehane's_ Equity: Doctrines & Remedies (4th ed, 2002) [36-010]. It is obvious, as the respondent had not purchased the property at the time that the appellants were carrying out the contravening work, that the respondent could not in any sense be regarded as having stood by whilst she observed the appellants infringing her legal rights. This ground also lacks merit.